Change to properties.

git-tfs-id: [https://tfs.codeplex.com:443/tfs/TFS15]$/Atomix;C39433
Rename brick to wall.

git-tfs-id: [https://tfs.codeplex.com:443/tfs/TFS15]$/Atomix;C39434
Anotate tile types with custom attributes for level editor.

git-tfs-id: [https://tfs.codeplex.com:443/tfs/TFS15]$/Atomix;C39435
LevelEditor: Add available tiles.

git-tfs-id: [https://tfs.codeplex.com:443/tfs/TFS15]$/Atomix;C39436