closes #661

* [android] Basic implementation of orientation change event and getter

#dasdsa

* [android] Check if fabAnimator is not null

* [android] Add configChanges prop to NavigationActivity in AndroidManifest

* [android] Fix duplicate declaration of onConfigurationChange

* [android] Use EventEmitter class to dispatch orientation change events

* Adds iOS callback for viewWillAppear/didAppear e.t.c.

* Adds in screen events on Android

* Fixed issue with rightButtons getting ignored in preference for empty Screen buttons

* Android screen lifecycle

This commit is contains a few changes and enhancements to the PR made by simon:

* Use getEventEmitter instead of sendNavigatorEvent
* Dispatch willDisappear and didDisappear events when pushing screens
* Dispatch willAppear and didAppear events when popping screen

fixes #800 #797

collapsingToolBarExpendedColor - determines the TitleBar color in expended mode
showTitleWhenExpended - defaults to true when expended color is defined.

* Fadeout translucent drawable when collapsing

* Change default scrim color to none
* Fade out translucent when collapsingToolBarCollapsedColor is not defined

Animate between translucent and solid background in collapsed titlebar

* Fixed issue with rightButtons getting ignored in preference for empty Screen buttons

* Fixes setting transparency of navigation bar using setStyle or when no transitionCoordinator

Ignore config changes in portrait and landscape activities