Rough implementation of mesh-based terrain rendering.
Merge remote-tracking branch 'origin/master' into meshTerrain
Merge remote-tracking branch 'origin/master' into meshTerrain
WIP mesh terrain upsampling.
Merge remote-tracking branch 'origin/master' into meshTerrain
Add Intersections2D.

This is an adaptation of STK's AgGxIntersections::ClipTriangleToPlane.
Merge remote-tracking branch 'origin/master' into meshTerrain
Add tests for Intersections2D.
Ongoing tile clipping.
Fix texture coordinates when upsampling.
Don't create duplicate vertices.
Add tests for upsampling.
Simpler and more correct upsampling.
Fix some upsampling problems.
Mark upsampled data as upsampled.
Fix jsHint warnings.
Merge remote-tracking branch 'origin/master' into meshTerrain
Add skirts.
Merge remote-tracking branch 'origin/master' into meshTerrain
Merge remote-tracking branch 'origin/terrainInspector' into meshTerrain