Experimenting with SVG.
Testing SVG events.
Merge remote-tracking branch 'origin/master' into playback
TimelineDemo - Add animation loop.
TimelineDemo tweaks.
Merge remote-tracking branch 'origin/master' into playback
Merge remote-tracking branch 'origin/master' into playback

Conflicts:
	Apps/TimelineDemo/TimelineDemo.js
Add a background behind widgets in TimelineDemo.
Imported buttons from SVG tests.
Started hookup of Playback widget to animationController.
Playback tooltips, unpause, and ressurect the timeline darker theme.
Tweak playback widget position, and flip ring animation inside out.
Make the large button hide the shuttle ring.
Hookup shuttle ring to animationController.
Style and behavior tweaks for playback and timeline widgets.
Shuttle ring angle updates during Playback.update().
Remove debug messages.
Tweak animation to make sure ring fully disappears.
Apply new Playback widget to CesiumViewerWidget.
Added a workaround for Firefox, only to reveal a new problem (which may or may not have resulted from auto-upgrading to Firefox 17).