tiles.rc syntax: allow inheriting of another tile's images/attributes

To inherit, just put the name of tile you want to inherit from in parenthesis
at the beginning of the specification.
E.g.

road-1-1     (road) roads/1-1 (road-north)(road-south)

will define a tile named "road-1-1", which first starts with all the images
and properties of tile "road" and then layers on top of that the 'road/1-1'
image, and then sets the 'road-north' and 'road-south' flags.

git-svn-id: https://micropolis.googlecode.com/svn/trunk/micropolis-java@754 d9718cc8-9f43-0410-858b-315f434eb58c

src/micropolisj/engine/Tiles.java

@@ -37,7 +37,7 @@ public class Tiles
 				continue;
 			}
 
-			tiles[i] = TileSpec.parse(i, rawSpec);
+			tiles[i] = TileSpec.parse(i, rawSpec, tilesRc);
 		}
 
 		for (int i = 0; i < tiles.length; i++) {