Bug 907013 - Implement AppWindowManager.

* Disable 3 marionette js tests because marionette seems having trouble on finding out alerts. Will file follow up bugs to re-enable them.
* Remove WindowManager and introduce AppWindowManager
* Introduce LayoutManager who knows and gethers the sizing info well.
* Fix OrientationManager issues.
* Abandon TransitionMixin and "Re"write an AppTransitionController for the use case of edge gesture -- let appWindow support multiple transitions.
* Abandon AuthenticationDialog and "Re"implement AppAuthenticationDialog
* AppWindow: Introduce subcomponents under appWindow
* AppWindow: Introduce broadcast for internal events, publish for external events.
* AppWindow: Introduce event handling mechanism by registeredEvents.
* Fix VisibilityManager issues.
* Change the mechanism in python based gaia-apps.
* More shared code between AppWindow and HomescreenWindow.
* More shared code between AppWindow and ActivityWindow.
* Add 100+ unit test functions.
* Isolate window.css from system.css
* Add a new event in KeyboardManager for continuos transition control.
* Add a developer settings for enabling simultaneous animation control.
* Add jsdoc support.