Edje_Edit: support new edje top block "size classes" with edje_edit API

Edje_Edit: support new edje top block "size classes" with edje_edit API

Plenty of new API:
edje_edit_size_classes_list_get - to return total list of size_classes inside of
loaded collection of groups
edje_edit_size_class_add - add new size class into loaded collection
edje_edit_size_class_del - deleting
edje_edit_size_class_name_set - renaming existing size class into something new
and some setters and getters for min and max (width and height) of size class.