(svn r581) -newgrf: Basic support for new stations - only waypoints supported now and only

the first custom one can be placed (no selector GUI, coming soon). This
also moves some global variables to {struct GRFFile} and reorders which
actions are processed in what stage, to get it all working together --
(pasky)

engine.h

@@ -84,8 +84,14 @@ struct SpriteGroup {
 	// XXX: Would anyone ever need more than 16 spritesets? Maybe we should
 	// use even less, now we take whole 8kb for custom sprites table, oh my!
 	byte sprites_per_set; // means number of directions - 4 or 8
+
 	// Loaded = in motion, loading = not moving
 	// Each group contains several spritesets, for various loading stages
+
+	// XXX: For stations the meaning is different - loaded is for stations
+	// with small amount of cargo whilst loading is for stations with a lot
+	// of da stuff.
+
 	byte loaded_count;
 	uint16 loaded[16]; // sprite ids
 	byte loading_count;