Summary:
this is just like elm_separator, just written for unified widgets.
This inherits from item, which has the advantage that this separator can
also be added into item container.
Reviewers: zmike, segfaultxavi
Reviewed By: segfaultxavi
Subscribers: cedric, #reviewers, #committers
Tags: #efl
Differential Revision: https://phab.enlightenment.org/D11125
