When sorting, some browsers like Chrome will lose the scroll position,
possibly because the sorting code is touching the DOM elements.
This fix saves the scroll position before sorting and sets it back
afterwards.
Old code first dit an ajax request to the avatar. Then a new image
object with the same src was created and since we do not cache avatars
yet :( this resulted in 2 sequential requests to the exact same URL
Now if you set the displayname it will first set the placeholder and
then load the avatar in the background. Only once this time!
* reason: nice to know before password change in user management
* restore is possible:
* encryption is disabled
* encryption is enabled, admin and user has checked the
restore option
* if not possible:
* highlight users row in red once the admin wants to change the password
* show also a little tipsy
* causes the first load after the initial load to hide some users in the viewport
and showing them again, but with a scrolled up viewport
* causes higher load for nearly never visible effects
* fixes#12962
* add disableEscape parameter to disable this functionality
* drop usage of escapeHTML() that is now done inside t()
* add unit test for escaped and not escaped placeholder
* proper JSDoc
* introduced new route settings/users/{id}/mailAddress
* kept old responses
* better error messages
* dropped lostpassword.php from settings/ajax
* cleaned up the UserList.add() and hand in user object instead of
each attribute as another parameter
* check for change permission of mail address
* proper response messages
* add switch to settings to show user backend
* user classes for headers and rows to unify the show/hide statement
* add user backend to response of user create request
* proper markup in settings area
This change will expose the user backend via the REST API which is a pre-requisite for https://github.com/owncloud/core/issues/12620.
For example:
````json
[{"name":"9707A09E-CA9A-4ABE-A66A-3F632F16C409","displayname":"Document Conversion User Account","groups":[],"subadmin":[],"quota":"default","storageLocation":"\/Users\/lreschke\/Programming\/core\/data\/9707A09E-CA9A-4ABE-A66A-3F632F16C409","lastLogin":0,"backend":"OCA\\user_ldap\\USER_LDAP"},{"name":"ED86733E-745C-4E4D-90CB-278A9737DB3C","displayname":"Hacker","groups":[],"subadmin":[],"quota":"default","storageLocation":"\/Users\/lreschke\/Programming\/core\/data\/ED86733E-745C-4E4D-90CB-278A9737DB3C","lastLogin":0,"backend":"OCA\\user_ldap\\USER_LDAP"},{"name":"71CDF45B-E125-450D-983C-D9192F36EC88","displayname":"admin","groups":[],"subadmin":[],"quota":"default","storageLocation":"\/Users\/lreschke\/Programming\/core\/data\/71CDF45B-E125-450D-983C-D9192F36EC88","lastLogin":0,"backend":"OCA\\user_ldap\\USER_LDAP"},{"name":"admin","displayname":"admin","groups":["admin"],"subadmin":[],"quota":"default","storageLocation":"\/Users\/lreschke\/Programming\/core\/data\/admin","lastLogin":"1418057287","backend":"OC_User_Database"},{"name":"test","displayname":"test","groups":[],"subadmin":[],"quota":"default","storageLocation":"\/Users\/lreschke\/Programming\/core\/data\/test","lastLogin":0,"backend":"OC_User_Database"}]
```
First step of a somewhat testable user management. - I know, the JSON returns are in an ugly format but the JS expects it that way. So let's keep it that way until we have time to fix the JS in the future.
