Addresses #80.

Caveat: I am not an Android developer. This code comes from a fork of the original RN WebView that we have been using in production for some time, so all credit goes to @Oblongmana: https://github.com/Oblongmana/react-native-webview-file-upload-android.

Setting up a DownloadManager for the WebView is pretty straightforward, as is adding any known cookies to the request. Most of the complication comes from the requirement after SDK 23 to ask the user for the WRITE_EXTERNAL_STORAGE permission. Unfortunately there is no mechanism to suspend the download request until permission is resolved so this code stores off the request and sets up a listener that enqueues the download once permissions are resolved so the user experience is really nice.

I didn't see anything in the way of tests or documentation that needs to be added for this change, so let me know if I missed anything. Thanks!

* add style doc in reference.md

* Update Reference.md

Adds a testimonial from Garrett McCollough (with his permission) to the README.

## [2.14.3](https://github.com/react-native-community/react-native-webview/compare/v2.14.2...v2.14.3) (2018-12-14)

### Bug Fixes

* **WKWebview:** Reverts [#134](https://github.com/react-native-community/react-native-webview/issues/134), fixes issue where keyboard dismiss would scroll to top ([#210](https://github.com/react-native-community/react-native-webview/issues/210)) ([9f37dde](https://github.com/react-native-community/react-native-webview/commit/9f37dde))

## [2.14.2](https://github.com/react-native-community/react-native-webview/compare/v2.14.1...v2.14.2) (2018-12-14)

### Bug Fixes

* **WKWebview:** Surface evaluateJavaScript errors ([#179](https://github.com/react-native-community/react-native-webview/issues/179)) ([ec469cf](https://github.com/react-native-community/react-native-webview/commit/ec469cf))

In the current code using `startInLoadingState` and `injectedJavaScript` will result in an infinite loading state if `injectedJavaScript` fails to evaluate for some reason. This adds a red box error explaining there was a failure to evaluate javascript. In my case this was do to the JS string not returning a valid type so I've added a that as a potential solution in the error message and added some documentation to the API Reference with some additional warnings.

To reproduce the existing behavior setup a webview with `startInLoadingState` and `injectedJavaScript` that returns an invalid type (in my case it returned a function). You should see an infinite loading state as `onLoadEnd` is never called.

Try the same with this branch and you'll get a nice red box error suggesting one potential solution to the problem.

![simulator screen shot - iphone 8 plus - 2018-11-28 at 15 09 25](https://user-images.githubusercontent.com/1944151/49193714-fccde100-f334-11e8-89dc-bf220e0adf.png)

## [2.14.1](https://github.com/react-native-community/react-native-webview/compare/v2.14.0...v2.14.1) (2018-12-14)

### Bug Fixes

* **WKWebview:** Fixed non-working iOS alert. ([#188](https://github.com/react-native-community/react-native-webview/issues/188)) ([41d9bdc](https://github.com/react-native-community/react-native-webview/commit/41d9bdc))

# [2.14.0](https://github.com/react-native-community/react-native-webview/compare/v2.13.0...v2.14.0) (2018-11-30)

### Features

* **Android Webview:** Support onShouldStartLoadWithRequest on Android ([#107](https://github.com/react-native-community/react-native-webview/issues/107)) ([b1b6626](https://github.com/react-native-community/react-native-webview/commit/b1b6626)), closes [#59](https://github.com/react-native-community/react-native-webview/issues/59) [#106](https://github.com/react-native-community/react-native-webview/issues/106) [#106](https://github.com/react-native-community/react-native-webview/issues/106)

This PR adds support for `onShouldStartLoadWithRequest` on android.

The initial PR was #59

The issue for this PR is: #106

fixes #106

# [2.13.0](https://github.com/react-native-community/react-native-webview/compare/v2.12.1...v2.13.0) (2018-11-25)

### Features

* **WKWebView:** [ios] Add allowsLinkPreview property to WKWebView ([#170](https://github.com/react-native-community/react-native-webview/issues/170)) ([731dd03](https://github.com/react-native-community/react-native-webview/commit/731dd03))

* [ios] Add ‘allowsLinkPreview’ property to iOS WKWebView.

* Add divider in docs

* Typo: add hyphen -> _allowsLinkPreview

## [2.12.1](https://github.com/react-native-community/react-native-webview/compare/v2.12.0...v2.12.1) (2018-11-22)

### Bug Fixes

* **types:** Fixing typing. ([#167](https://github.com/react-native-community/react-native-webview/issues/167)) ([65bd972](https://github.com/react-native-community/react-native-webview/commit/65bd972))

so happy to see there is typing in the newest release.
I added back WebViewIOSLoadRequestEvent which also exist in react-native typing and fix startInLoadingState which should be boolean.

# [2.12.0](https://github.com/react-native-community/react-native-webview/compare/v2.11.0...v2.12.0) (2018-11-22)

### Features

* **types:** Post message types ([#166](https://github.com/react-native-community/react-native-webview/issues/166)) ([0ff0fd3](https://github.com/react-native-community/react-native-webview/commit/0ff0fd3))

# [2.11.0](https://github.com/react-native-community/react-native-webview/compare/v2.10.0...v2.11.0) (2018-11-22)

### Features

* **WKWebview:** [ios] Add 'pagingEnabled' property to the iOS WKWebview ([#165](https://github.com/react-native-community/react-native-webview/issues/165)) ([4870e1f](https://github.com/react-native-community/react-native-webview/commit/4870e1f))

# [2.10.0](https://github.com/react-native-community/react-native-webview/compare/v2.9.0...v2.10.0) (2018-11-21)

### Features

* **Android:** Support Android file upload ([#60](https://github.com/react-native-community/react-native-webview/issues/60)) ([752a5b2](https://github.com/react-native-community/react-native-webview/commit/752a5b2)), closes [#33](https://github.com/react-native-community/react-native-webview/issues/33)

Fixes #33 

I could really use some help from an Android developer on this one, because I just "made it work", don't know how to "make it work good".

Some things that should be reviewed:

- [ ] validate Android 5.0 devices (my emulator work, but outputs some weird sounds; a Galaxy 4 I tested on crashes)
- [ ] validate Android 5.1 devices (emulator works, couldn't find a real device)
- [ ] how to handle File Extensions? (https://www.w3schools.com/tags/att_input_accept.asp)

I'm sure that there's more refactoring to be done, so any help and advice would be appreciated.

# [2.9.0](https://github.com/react-native-community/react-native-webview/compare/v2.8.1...v2.9.0) (2018-11-21)

### Features

* **types:** added missing types ([#157](https://github.com/react-native-community/react-native-webview/issues/157)) ([f70700d](https://github.com/react-native-community/react-native-webview/commit/f70700d))

## [2.8.1](https://github.com/react-native-community/react-native-webview/compare/v2.8.0...v2.8.1) (2018-11-20)

### Bug Fixes

* **WKWebView:** Fix the message handle bug. ([#143](https://github.com/react-native-community/react-native-webview/issues/143)) ([2b9292e](https://github.com/react-native-community/react-native-webview/commit/2b9292e))

* fix webview always recreate

* fix webview always recreate

* code format

* Update RNCWKWebView.m

* @bugfix fix the message handle problem

Added a Contributing.md file and moved contributor notes there. Also added @empyrical. :tada:

* Add fix for keyboard dismiss leaving viewport shifted in iOS 12

* Readme - added note about Expo and added troubleshooting section

# [2.8.0](https://github.com/react-native-community/react-native-webview/compare/v2.7.1...v2.8.0) (2018-11-19)

### Features

* **WKWebview:** Add fix for keyboard dismiss leaving viewport shifted in iOS 12 ([#134](https://github.com/react-native-community/react-native-webview/issues/134)) ([5425039](https://github.com/react-native-community/react-native-webview/commit/5425039))

## [2.7.1](https://github.com/react-native-community/react-native-webview/compare/v2.7.0...v2.7.1) (2018-11-19)

### Bug Fixes

* **WKWebview:** Fixed for supporting mediaPlaybackRequiresUserAction option under iOS 10. ([#129](https://github.com/react-native-community/react-native-webview/issues/129)) ([c0c0116](https://github.com/react-native-community/react-native-webview/commit/c0c0116))

# [2.7.0](https://github.com/react-native-community/react-native-webview/compare/v2.6.0...v2.7.0) (2018-11-19)

### Features

* **WKWebview:** Add 'userAgent' property to the iOS WKWebView. ([#112](https://github.com/react-native-community/react-native-webview/issues/112)) ([2ec5fa5](https://github.com/react-native-community/react-native-webview/commit/2ec5fa5))

* Add 'userAgent' property to the iOS WKWebView

* Update 'userAgent' reference docs.

# [2.6.0](https://github.com/react-native-community/react-native-webview/compare/v2.5.0...v2.6.0) (2018-11-19)

### Features

* **typings:** Add typescript definitions ([#95](https://github.com/react-native-community/react-native-webview/issues/95)) ([715fe61](https://github.com/react-native-community/react-native-webview/commit/715fe61))

Typescript definitions are based on flow
Tested them a bit in my project
I think couple of event types are screwed in flow definitions (synthetic/non-synthetic are mixed), tried my best to test which events are really received.

# [2.5.0](https://github.com/react-native-community/react-native-webview/compare/v2.4.3...v2.5.0) (2018-10-21)

### Features

* **WKWebview:** [iOS] Add 'allowsBackForwardNavigationGestures' property ([#97](https://github.com/react-native-community/react-native-webview/issues/97)) ([7f35344](https://github.com/react-native-community/react-native-webview/commit/7f35344))

## [2.4.3](https://github.com/react-native-community/react-native-webview/compare/v2.4.2...v2.4.3) (2018-10-18)

### Bug Fixes

* **semantic-release:** Added Missong devDeps for CI ([1394c7d](https://github.com/react-native-community/react-native-webview/commit/1394c7d))
* **semantic-release:** Use git plugin to auto commit ([c727dd9](https://github.com/react-native-community/react-native-webview/commit/c727dd9))

Bumped deps version to use new format

Fix cocoapods install error and warning.
```
Fetching podspec for `react-native-webview` from `../node_modules/react-native-webview`
[!] The `react-native-webview` pod failed to validate due to 1 error:
    - WARN  | attributes: Missing required attribute `license`.
    - ERROR | version: The version of the spec should be higher than 0.
    - WARN  | license: Missing license type.
    - WARN  | source: Git sources should specify a tag.
```

* Fixes #81 
* Fixes #72

* add hideKeyboardAccessoryView option

* add hideKeyboardAccessoryView prop to reference