Adds foreground layer support ( by property )
Converts images to foreground in new-abedtown
Merge branch 'master' into foreground_tile_layers
Merge branch 'master' into foreground_tile_layers

Conflicts:
	src/maps/new-abedtown.tmx
Convert image to foreground for castle entrance
Fix Issue #721
Merge pull request #868 from Ciziu/floorspace_bugfix

Fixes #721
Changes tmx:draw api
Merge pull request #859 from jhoff/foreground_tile_layers

Adds foreground layer support ( by property )