Added MeshFilters.combine for batching
Added batching to polygons with holes
Merge branch 'master' into batching
Minor Polygon.js cleanup
Merge branch 'master' into batching
Start of CesiumViewerWidget replacement.
Merge cv to batching
Merge remote-tracking branch 'origin/master' into batching
Start of generic primitive and appearance
Merged master to batching
Merge branch 'master' into viewer
Use buildModuleUrl instead of require.toUrl.
Merge branch 'master' into viewer
Merge branch 'dataSources' into viewer
Expose data sources collection and drive the display.
Ongoing Viewer widget work.

Add ability to control which widgets are created at construction time.  Also properly implement destroy and clean up some Timeline code to allow it to be destroyed.
Merge master to batching
Fixed destroying vertex array
Fixed modelMatrix in generic primitive
Added geometry types