Move and resize the scene widget.
Merge remote-tracking branch 'origin/sceneModeWidget' into scene-icons
Experimenting with some simpler graphics and a shorter tooltip.  Not happy with either yet...
Merge remote-tracking branch 'origin/sceneModeWidget' into scene-icons

Conflicts:
	Source/Widgets/Dojo/CesiumViewerWidget.css
	Source/Widgets/Dojo/CesiumViewerWidget.html
Redesigned icons. No morph icon or lighter theme yet.
Morphing icon.  Not very exciting.
Add lighter theme.
SceneMode widget now knows "future" morph mode.

This commit adds code to address #588 and will need extra code
review from @mramato and @bagnell.  It can be backed out if
it's too disruptive, but I like the UI effect.
Merge pull request #589 from AnalyticalGraphicsInc/scene-icons

Scene mode widget icons