Move various files to their new homes.
Move a bunch of terrain-related types to Core.
Sort requires.
Remove Scene dependency in TilingScheme.js.
Factor Renderer/Scene stuff out of TerrainProvider.
Update CHANGES.md.
Fix test failures.
Fix require order.
Merge remote-tracking branch 'origin/moveTerrainToCore' into quadtreePrimitive

Conflicts:
	Source/Core/GeographicTilingScheme.js
	Source/Core/TilingScheme.js
	Source/Scene/Globe.js