elm_win: make it possible to specify alpha window in the theme directly.
elm_win: make it possible to specify alpha window in the theme directly.

tasn/elementary,rvandegrift/elementary,tasn/elementary,FlorentRevest/Elementary,tasn/elementary,FlorentRevest/Elementary,FlorentRevest/Elementary,rvandegrift/elementary,FlorentRevest/Elementary,rvandegrift/elementary,rvandegrift/elementary,tasn/elementary,tasn/elementary