Summary:
Efl.Ui.Layout namespace is removed to keep consistency with other
widgets.
Consequently, "Efl.Ui.Layout.Object" is renamed to "Efl.Ui.Layout" and
"Efl.Ui.Layout." is renamed to "Efl.Ui.Layout_".
Reviewers: segfaultxavi, bu5hm4n, cedric
Reviewed By: segfaultxavi
Subscribers: #reviewers, #committers, SanghyeonLee, woohyun
Tags: #efl
Differential Revision: https://phab.enlightenment.org/D7291