webadmin: Made profile name checks consistent

Fixed the frontend validation to be as restrictive as the backend one
(e.g. not allowing dots), as well as added a frontend validation of
the profile names in the add/edit network dialog.

Change-Id: Ided5e902faae928608a7558a08ed1768e3d8cb81
Bug-Url: https://bugzilla.redhat.com/1012032
Signed-off-by: Lior Vernia <lvernia@redhat.com>