Add CreateAsset options for GameResource types
Remove a bunch of unused p4 stuff
Remove a bunch more unused p4 stuff
-AssetTargetGameRoot isn't ever going to be used
Don't store CResourceAssetTypeInfo on ResourceCompilerCentext, just store the data we need (extensions + compiler name)
Pass InitializeCompilerForFilename to c#, expose some of IResourceCompilerContext
Cleanup ManagedResourceCompiler