Material support for DynamicPolyline

Originally, we hardcoded DynamicPolyline to always us a PolylineOutline material type because we did not support general materials in CZML.  Now that the DynamicScene and CZML processing are decoupled, the lack of CZML support for it doesn't matter.  This allows users to use any Material we support in DynamicScene that also supports polylines (currently just ColorMaterialProperty and PolylineOutlineMaterialProperty but others are trivial to add).
Merge branch 'master' into dynamicPolyline-materials

Conflicts:
	CHANGES.md
	Source/DynamicScene/DynamicPolylineVisualizer.js
Fixes after merge.
Merge branch 'master' into dynamicPolyline-materials
Fix my sloppy mistakes found during review.
Merge pull request #1168 from AnalyticalGraphicsInc/dynamicPolyline-materials

Material support for DynamicPolyline