this commit marks step one of The Gengrid & Genlist Unification Project. these poor...

this commit marks step one of The Gengrid & Genlist Unification Project. these poor widget brothers were separated at birth, never knowing that they were almost exactly the same.
from here, it should be trivial to continually move more and more code into elm_gen.c and reduce duplication.
ideally we should be aiming for an elm_gen_* api where you differentiate between list/grid with style or something since the apis are almost identical

git-svn-id: svn+ssh://svn.enlightenment.org/var/svn/e/trunk/elementary@64245 7cbeb6ba-43b4-40fd-8cce-4c39aea84d33