Use Game Maker conventions for resource names

game/art/game_player.h

@@ -3,6 +3,6 @@
 
 #include "sys/sys.h"
 
-extern sys_spritesheet game_player;
+extern sys_spritesheet spr_game_player;
 
 #endif  // CROCPARTY_GAME_PLAYER_H

game/art/game_tiles.h

@@ -3,6 +3,6 @@
 
 #include "sys/sys.h"
 
-extern sys_spritesheet game_tiles;
+extern sys_spritesheet spr_game_tiles;
 
 #endif  // CROCPARTY_GAME_TILES_H