* boards/sounds/scroll.wav: added from Tuxpaint
	* src/boards/crane.c: (item_event), (arrow_event), (place_item),
	(select_item): added audio effects
	* src/boards/gtans_callbacks.c:
	(on_wdrawareagrande_configure_event),
	(on_wdrawareagrande_button_press_event),
	(on_wdrawareapetite_configure_event), (on_arrow_clicked),
	(on_show_clicked), (on_outline_clicked), (on_symetry_clicked),
	(on_rotation_clicked): added audio effects
	* src/boards/hanoi.c: (hanoi_create_item), (item_event): added audio effects
	  fixed non centered title background area.
	* src/boards/submarine.c: (submarine_next_level),
	(submarine_create_item), (update_timeout_slow), (open_door): added a treasure
	 that you must pickup first, then the door open itself.
	* src/gcompris/gcompris.c: (gc_init): now intro sounds are not played is a specific
	activity is requested.