edje: make it possible for all upper layer function to query the exact same file.

edje: make it possible for all upper layer function to query the exact same file.

With Eina_File we now can pass an efficient handler accross library boundary. Edje
and all underlayer already use it to avoid race condition when setting an Edje object.
Elementary and Enlightenment are still exposed to some potential race condition when
an Edje file is modified underneath there feet. With the following set of function it
should now be possible to avoid those race condition to:
edje_mmap_data_get
edje_mmap_collection_list
edje_mmap_collection_list_free
edje_mmap_group_exists