Transfer Ownership

closes #3364 (special thanks to @jaswilli)
closes #3087
- added modal
- added controller
Preventing rogue modals from popping up when hitting the enter-key

closes #3352
- adding a ```type``` attribute to buttons inside form in the settings section
- scanning the rest of the project to find any other buttons w/a missing attribute
Fix incorrect error

closes #3373
- added check if role is already assigned
- added check for unknown fields to fixDates/fixBools
- permissions are not implemented yet, so everyone is able to edit
owner ;-)
Wrong Facebook page URL
Merge pull request #3381 from SiR-DanieL/patch-1

Wrong Facebook page URL
Merge pull request #3359 from morficus/issue-3352

Preventing rouge modals from popping up when hitting enter-key in settings section
Merge pull request #3362 from sebgie/issue#3087-2

Transfer Ownership
Merge pull request #3380 from sebgie/issue#3373

Fix incorrect error
Improve handling of users and roles in admin

Closes #3083 Refs #3229
- Populates the dropdown list in the invite user menu with the
  list of roles a user is permitted to create.
- Users API now checks the invite user request for allowed roles.
- Change API response from 200 to 201 on successful invitation.
- Change API response from 500 to 201 when the user was created but
  the email was not sent.  The client will show a warning notification
  when it sees 'invite-pending' as the new user's status.
- Add support for "?status=all" to the /users endpoint.
- Refactor the route and controller for the /settings/users page so
  that there's only one network API call to load users instead of two.
Merge pull request #3388 from jaswilli/issue-3083

Improve handling of users and roles in admin
Signin: Proper notification if user not found

closes #3374
- If user object is returned but undefined, we'll display a
human-readable
error notification (user model)
- If user object is returned, but the user is inactive or invited (but
not
activated), we'll display a human-readable error notification