BUG: Users don't get status update/change email notification when they are added to a group or group changes.

1. Using Django portal the user created a local account, providing institute email, IU mail.
2. user didn't get a mail when added in to an active user group.

TODO

• [x] Send email when user added to group in GroupViewSet and IAMUserViewSet
• [x] Update Manage Users group management to have a Submit button instead of immediately adding user to group when check box is checked
• [x] Set Reply-To on the notification email to the PORTAL_ADMINS. This way the user can reply to the email if they have any questions and the reply will go to the portal admins.
• [x] Only send one email when user added to more than one group at the same time. Only applied to IAMUserViewSet.