* Added a dropdown to video & audio settings
* Changes to ListHelper:
** Limits resolution when code requests the default video resolution
** Limits audio bitrate when code requests the default audio bitrate
** Removed some dead code and did some cleanup
** Make methods private/protected to help understand what was in use
** The code now chooses one format over an other using a simple raking system defined in array constants. I realized I needed to do this in order to choose the most efficient video stream. I did my best to evaluate the video and audio formats based on quality and efficiency. It's not an exact science.
** Made changes to the tests to support my changes
-Added button to open captioning settings activity from appearance settings.
-Modified player captions to use custom caption style when captioning manager is enabled.
-Removed caption size settings from appearance settings.
-Changed tempo and pitch button in service player activity and tempo button in main video player to open speed control dialog.
-Changed LIVE button to be no longer clickable when player position is at or beyond default position.
-Changed main video player to use AppCompatActivity rather than Activity.
-Fixed video player tempo button not updating when player speed parameters change.
-Fixed player crashing on lower sdk versions due to no MediaButtonReceiver, added intent back to manifest.
-Fixed inconsistent gradle library naming.
-Fixed stetho dependencies incorrect version.
-Changed play queue items to display service names.
-Fixed Soundcloud playlist not fitting thumbnail.
-Refactored image display options to follow uniform behavior.
-Refactoring and style changes on audio reactor and media button receiver.
-Added button to wipe metadata cache.
-Added more paddings on player buttons.
-Added new animations to main player secondary controls and play queue expand/collapse.
-Refactored play queue item touch callback for use in all players.
-Improved MediaSourceManager to better handle expired stream reloading.
-[#1186] Changed live sync button text to "LIVE".
-Removed MediaSourceManager loader coupling on main players.
-Moved service dependent expiry resolution to ServiceHelper.
-[#1186] Fixed livestream timeline updates causing negative time position.
-[#1186] Fixed livestream not starting from live-edge.
-Fixed main player system UI not retracting on playback start.
- Import subscriptions from YouTube and SoundCloud (all services that the extractor support)
- Import/export a JSON representation of the subscriptions
- [Minor] Remove some javax annotations in favor of the one provided by the android support library
-Added toggle to enable auto-queuing.
-Modified main video player to only pause the video onPause.
-Fixed main video player not saving play queue state onStop.
-Improved player sync calls to recognize different metadata updates.
-Changed MediaSourceManager to synchronize only after timeline changes and reenabled multiple sync calls to player.
-Renamed listener and synchronization methods related to MediaSourceManager.
-Added sync buttons on live streams to allow seeking to live edge.
-Added custom cache key for extractor sources to allow more persistent reuse.
-Refactored player data source factories into own class and separating live and non-live data sources.
