* boards/skins/default/skin.xml: added and changed colors for erase
	* boards/skins/pink/skin.xml: added and changed colors for erase
	* src/boards/erase.c: (erase_next_level), (erase_create_item),
	(game_won), (item_event): based on an idea of Zsolt, added a 2 times and 3 times shoot items
	* src/gcompris/.cvsignore: fixed.