win: Added internal documentation about elm_win_rotation_set and elm_win_rotation_with_resize_set().
win: Added internal documentation about elm_win_rotation_set and elm_win_rotation_with_resize_set().

This is for efl developers not app developers so it goes to elm_win.c
Without knowing this, it is very tricky to understand the concept of
this api.

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