elementary - modified item_del_pre_hook function prototype.

elementary -  modified item_del_pre_hook function prototype.

Now it returns the bool value to free the widget item.

Some widget items(i,e genlist) should not be deleted directly when elm_object_item_del is called.
So, if the pre_hook function returns EINA_FALSE, then the widget item will not be deleted.

git-svn-id: svn+ssh://svn.enlightenment.org/var/svn/e/trunk/elementary@67565 7cbeb6ba-43b4-40fd-8cce-4c39aea84d33

Conflicts:

	src/lib/elc_naviframe.c