efl: split efl_ui_range into display and interactive
display contains properties that are used to manipulate the display.
Range_step is a interactive property since it manipulates the way the
user interacts with this widget. This resolves a few unimplemented APIs.
Reviewed-by: Xavi Artigas <email@example.com>
Differential Revision: https://phab.enlightenment.org/D7715