The following PR introduces improved support for Context api and other api's which wrap the root view.

## Context api
Navigation.registerComponent('navigation.playground.ContextScreen', () => (props) => (
  <TitleContext.Provider value={'Title from Provider'}>
    <ContextScreen {...props} />
  </TitleContext.Provider>
), () => ContextScreen);

## Redux
Navigation.registerComponent('navigation.playground.ReduxScreen', () => (props) => (
  <Provider store={reduxStore}>
    <ReduxScreen {...props} />
  </Provider>
), () => ReduxScreen);

## Plain Component - not changed
Navigation.registerComponent('navigation.playground.MyScreen', () => MyScreen);

This PR also upgrades the TypeScript version to 3.2.0 and RN version used in the playground app to 0.57.7

* New Android build flavor - `reactNative57_7`
* Unit test coverage is disabled, for some reason it broke after upgrading to RN 0.57.7

* Fix typo in setStackRoot animation docs

* Use 'enabled' instead of 'enable'

This commit fixes #4045, which revealed a design flaw in the options applying logic.
Child options are applied when a ViewController.onViewAppeared is invoked.
A ViewController's appearance is determined from a GlobalLayoutListener.

Consider the following layout hierarchy:
BottomTabs > Stack > Component

onViewAppeared will be triggered for the BottomTabs first, then for the Stack and last for the component.
This means that if the Stack and the Component options will be applied consecutively which in some cases
might case flickering, mostly when drawBehind options are applied.

* Renamed RNNRootViewProtocol to RNNParentProtocol and added RNNLeafProtocol

* fixed unit test

* Better options resolving

* Revert "Revert "Refactor options (#3962)""

This reverts commit c266041b85.

* Revert "Revert "Fixes shared element transition""

This reverts commit 005f039f7c.

* Revert "Revert "Adresses #3963 - stack options applied to children""

This reverts commit be09cb0e9a.

* Revert "Revert "Added unit test coverage for RNNNavigationController""

This reverts commit 199cebd221.

* Merge stack options

This commits adds support for merging stack options by the stack’s componentId

Also while I’m at it - use fade animation when setting root

* Merge BottomTabs options

Merge BottomTabs options when calling mergeOptions with BottomTabs componentId

* Fixes options

* Refactor peek and pop

* Rollback some XCode stuff

* Added tests for touchablePreview event

* Also fixing searchbarcancelpressed event

* Making sure tests work

This reverts commit 4c519acae8.

* Refactor peek and pop

* Rollback some XCode stuff

* Added tests for touchablePreview event

* Also fixing searchbarcancelpressed event

* Refactored bottomTab and bottomTabs

* Initial commit before switching to our fork of AHBottomNavigation

* Bump AHBottomNavigation version

* More work on BottomTab options

Need to merge some child options when a child is attached to parent

* Fix tests

* DefaultOptions refactor

* defaultOptions are now merged before applying options
* Handle BottomTab options in dedicated presenter
* Create BottomTabs in BottomTabsController.createView() instead of constructor

* Set bottomTab TypeFace

* Update Android installation guide

* fixed unit tests

* Fix unit tests

Kind of a workaround

* Handle NPE in getPreferredHeight

If a view hasn't been attached yet, return 0 height

* Apply BottomTab text and icon color individually

wix-playground/AHBottomNavigation does not support setting color for the entire tab (icon and text),
instead it supports setting color individually to text and icon. Another change is that it no longer supports
default color for icons. If icon color is undefined - it won't tint the icon.

* Add getCurrentChild to ParentController contract

* Clear backButton when setting stack root

* Add  ViewController.resolveCurrentOptions

resolveCurrentOptions merges the controllers options with all of its current children

* StackController refactor

* Create pushed child view only in StackController.createView
* When initialising a stack with multiple children, only create the top child's view
* StackController constructor now accepts children
* When pushing child to stack, apply options that change LayoutParams

* Apply BottomTabs layout options when tab views are created

* bototmTab changes in iOS

* options fix

* Fixes options propagating

* add addicional options to tabbar

* fix tests

* [ios11+] Add searchBar option for topBar

* Fix formatting and linter issues

* Add docs about topBar.searchBar

* Fix missing semicolons

* Revert prettier changes

* Add js tests for onSearchBarUpdated to achieve 100% coverage

* Mark searchBar test as :ios: specific

This option allows to control when tab titles are displayed

* showWhenActive: when a tab is focused
* alwaysShow: show regardless of which tab is in
* alwaysHide: never show tab titles

This commit also changes the way TopTabs options are handled. As the TabLayout
is part of the TopBar, it's the StackControllers responsibility to set TopTabs options.

* V2: Peek and pop

* Add event when preview is dismissed in non commit mode

* tslint

* Refactor playground. Document preview api

* Added width prop

* Implement hybrid push/preview button

* Fixing small linting errors

* Work in progress

* Arbitary changes

* Improvements on API

* Cleanup RNNSplitViewController, allow mergeOptions

* Added documentation and better playground example

* Adding tests for coverage

* Find out why this test is failing.

* Only show split view on iOS

* Add test back in

* setRoot({root:{}})

* support setRoot with root, modals, overlays

* Update setRoot calls in playground app to new api

* Update setRoot on Android to new api

currently only supporting root node

* Update setRoot on iOS to new api

* fix unit tests

This commit removes NavigationOptionsListener as it was not needed anymore.
As a result, it uncovered a few issues which this commit also aims to fix.

* Set SideMenuController as parent of left, right and centre controllers
* Select tab by id with tabSelector interface
* mergeOptions now also applies options after merge - in ViewController base class
* Pull presentation logic from ComponentLayout to ComponentViewController

* migrate js and java to mergeOptions

* migrate ios to mergeOptions

* Refactor TopBar options, introduce title options

* Update background to new api

* Refactored topBar options on iOS

* Initial react component in TitleBar android

* set height to react view in TitleBar

* fix tests and lint

* ios unit tests fix

* External Component implementation

* Limit External component e2e to Android for now

* Make detox android test suit pass

Disabled emulator animations due to limitation of espresso/detox which can't wait until
a push/pop animation ends

* Fix orientation parsing and enable detox orientation tests

* remove only

* Fix BottomTabs testId

* Support user orientation

* Fix rightButtons testId

* Add Modals tests

* e2e fix ios

* custom viewController support

* native component support and e2e

* custom viewController support

* native component support and e2e

* unit test fix

* Rename TopBar.animateHide to animate

also fix some options in playground app

* Consolidate topBar visibility in childWillDisappear

* Rename BottomTabs.animateHide to animate

* generate id only when not already provided

* allows passing id

* fixes #2652

* Use AHBottomNavigation for BottomTabs

* Process passed options for all layout types

Static options are still processed only for components

* ios e2e fix

* Update RNNNavigationController.m

Continued work on Android

* Rename TopTabsLayout to TopTabsViewPager
* Pass ScrollEventListener from component
* Change ViewController.view to protected
* Don't keep ref to view in ComponentController
* Pull IReactView and ReactViewCreator to separate classes
* Ensure ToolBar.menu is created before clearing menu items
* Unmount react view before destroy
* Let TopTabsController set mediator in view visibility handling