Fixes #1938 Closes #1900

This commit fixes two issues found in #1838. Fixes #1924
1. Keeps calling the deprecated reactInstanceManager methods when host is cleared
    to not introduce undesired behavior when clearHostOnActivityDestroy return true.
2. call onHostDestroy and onHostPause only if react context exists or is being created.

* remove unused code from tabStyle

* improve dummy screen ui

* set list screen translucent navigation bar

* make RCCToolBarView to composite the UIRootView inside

* add list screen for debug behaviours

* add dummy screen

* ui changes in ListScreen

* add push list screen function without add it to the button to the screen

* add and comment push list screen row

This only happens when you are using react-native@0.48.3, and your XCode is in version 9.0

* android oreo overdraw fix

* apply top bar title color

* update readme

* update formatting

* merge v2

* navigation oprtions formatting

* font size props

* update test

* ci fix

* rm global variable

* font size

* update readme

* playground

* after merge fix

* typeface in progress

* presenter skeleton

* test fix

* rm presentation

* options presenter

* typeface

* readme

* test refactoring

* typeface loader tests

* presenter skeleton

* test fix

* rm presentation

* options presenter

* test refactoring

* Update the comment for tabsStyle in Android

* for -> on

* Update top-level-api.md

Fixes #1844

This commit adds support for fade and slide-horizontal animations for modals and a few other animation related changes:

* Support defining animationType when calling dismissModal
* Support fade and slide horizontal animations for modals
* Slightly reworked current screen animations timings
* Fixed slide-horizontal x offset and removed alpha

* android oreo overdraw fix

* apply top bar title color

* update readme

* update formatting

* merge v2

* navigation oprtions formatting

* font size props

* update test

* ci fix

* rm global variable

* font size

* update readme

* playground

* after merge fix

This is a breaking change and has to be opt-in. To prevent host.clear from being called,
Override `clearHostOnActivityDestroy` in MainApplication and return false:

```java
    @Override
    public boolean clearHostOnActivityDestroy() {
        return false;
    }
```

If host isn't cleared, the next time the app is opened react context might still be initialized.
In this case we emit appLaunched event which has to be handled in Js:

```js
  Promise.resolve(Navigation.isAppLaunched())
      .then((appLaunched) => {
        if (appLaunched) {
          startApp();
        }
        new NativeEventsReceiver().appLaunched(() => {
          startApp();
        });
      })
```

* android oreo overdraw fix

* apply top bar title color

* update readme

* update formatting

* merge v2

* navigation oprtions formatting

* update test

* ci fix

* rm global variable

* remove obsolete method

This converts from using a deprecated attribute.

* add disabledButtonColor in order to set navigation button disabled color

* add disabledButtonColor to the docs

* Added v2 docs

* Move docs around

* Update _sidebar.md

* Update README.md

* Delete

* Remove usage docs (it was duplicated)

* Fixed sidebar links

* Moved the readme back to the root

* Added v2 docs

* Move docs around

* Update _sidebar.md

* Update README.md

* Delete

* Remove usage docs (it was duplicated)

* Fixed sidebar links

* Added v2 docs

* Move docs around

* Update _sidebar.md

* Update README.md

* Delete

* Remove usage docs (it was duplicated)

This reverts commit 082a65d791.