Make Polyline and Path use materials

Get rid of most invidual properties and use materials instead
Add PolylineOutline and PolylineGlow materials.
Split Material.jsonschema into two files

PolylineMaterial.jsonschema - Materials applicable to polylines and paths.
Material.jsonschema - materials applicable to everything else.

This has no affect on the resulting CZML, it just makes it impossible to write out a material that is incompatible with it's intended object.
Forgot to save sln.
Make materials more closely match Cesium

Grid and Image materials split out Cartesian2 properties into multiple individual properties.  In practice this is not very useful and can bloat the size of the CZML if both are chaning.  This change also makes it easier to implement in Cesium and gets rid of some workarounds we were currently using.
Merge pull request #73 from AnalyticalGraphicsInc/material-cleanup

Make materials more closely match Cesium
Merge remote-tracking branch 'origin/master' into polyline-materials
Merge pull request #72 from AnalyticalGraphicsInc/polyline-materials

Make Polyline and Path use materials
Merge remote-tracking branch 'origin/master' into follow-surface

Conflicts:
	DotNet/CesiumLanguageWriter/Generated/PolylineCesiumWriter.cs
	Java/CesiumLanguageWriter/translatedSrc/cesiumlanguagewriter/PolylineCesiumWriter.java
	Schema/Polyline.jsonschema