In this patch:
- Changed the Group Edit 'General' section and added the 'Feedback
notifications' options.
- Changed the Group Edit 'General' section and altered the 'Shared
page' option from tickbox to select options.
- Changed the CommentFeedback to be able to notify multiple users in a
group
- Changed the CommentFeedback to be able to send message in the
institution lang if needed.
- Adjusted group_get_editroles_options() to allow it to return a non
associative array

Signed-off-by: Robert Lyon <robertl@catalyst.net.nz>

Change-Id: Ia2e995c51aa08610945788e55c809b3c650dcd17