The call to UserList.add() was wrong and was passing "user.lastLogin"
as the sort argument which would cause the list to be resorted over and
over again for every added item after loading the next page of users.
Users page lazy multiselect group dropdowns
Instead of pre-rendering all multiselects with lots of group entries,
the current groups are now displayed as simple labels.
Behind the labels there is a pencil icon like for other fields.
When clicking the pencil icon, the dropdown will be spawned and will
open itself.
Upon closing of the dropdown, the label comes back with the updated
selection and the dropdown is destroyed.
Extra non-available groups also in list
Fix group sorting in user list group selection
* Password Update Notification
Added an IF ELSE statement to ensure that feedback is provided to the
user on successfully updating a user password in settings.
* Password Update Success Message
Updated the password update success message
jquery.fileupload offers the [`pastezone`](https://github.com/blueimp/jQuery-File-Upload/wiki/Options#pastezone) functionality. This functionality is enabled by default and if somebody copy-pastes something into Chrome it will automatically trigger an upload of the content to any configured jquery.fileupload element embedded in the JS.
This implementation triggers some problems:
1. The pastezone is defined globally by default (🙈). So if there are multiple fileupload's on a page (such as in the personal settings) then stuff is going to be uploaded to all embedded uploads.
2. Our server code is not able to parse the data. For example for uploads in the files app we expect a file name which is not specified => Just an error is thrown. You can reproduce this by taking a file into your clipboard and in Chrome then pressing <kbd>CTRL + V</kbd>.
3. When copy-pasting some string from MS Office on the personal page a temporary avatar with said content is created.
Considering that this is anyways was never working at all and causes bugs I've set the `pastezone` to `null`. This mens that upload via copy and paste will be disabled.
Lesson learned: Third-party JS libraries can have some weird details.
If an app is getting enabled in the web UI, an ajax call is now made to
make sure the server still works. If it doesn't, it sends an emergency
app disabling call to disable the breaking app.
