Fixes new avatar selection in master half, other half will work when https://github.com/owncloud/core/pull/14266 has get merged.

Shocking to see how much places in our code do it wrong 🔫

* 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 logSettingsController

add download logfile button

move getEntries to LogSettingsController

move set log level to logsettingscontroller.php

add warning if logfile is bigger than 100MB

add unit test for set log level

fix typecasting, add new line at EoF

show log and logfile download only if log_type is set to owncloud

add unit test for getFilenameForDownload

* 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

* supply mail address
* send mail with username and URL to that mail address
* option to temporary enable this feature

* 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.

to fix issue #11959

Add switch to enforce SSL for subdomains

Add unit tests

Add test for boolean values

Camel-case

Fix ugly JS

Changed the column header to "Group Admin for" and the default value of
the multiselect box to "no group" if user is not a groupadmin for any
group.

filter installed and not-installed apps properly

kill unneeded file

load category 'Installed' on page load

adding documentation links

new apps mgmt: first style adjustment

apps mgmt: only show license and preview if they exist

adding buttons

new apps mgmt: fix for mobile

use app icon if available

new apps mgmt: position enable/disable toggle to the right

new apps mgmt: proper display of icons or previews

new apps mgmt: fix loading spinner

reenable group selection for apps

new apps mgmt: position enable button normally again

new apps mgmt: clarify wording from 'Installed' to 'Enabled'

reintroduce enable/disable

Move rating image path generation to client-side

Move expression outside of l10n

fix group handling

add buttons for 'More apps' and 'Add your app' again

disable changed date of app for now

adding recommended label

style 'Recommended' app tag

fixing php warning

sort by rating

adding meta-category 'Recommended'

 Only show existing documentation links

lacy loading of screenshots

making group based app activation work again

adding support to get the app icon not only by the app name but also simply by the fixed name 'app.svg'

adding app.svg for all core apps

query string '?installed' is not longer needed

update and uninstall is back + error feedback

remove unneeded parameter

fix alignment of 'recommended' label

- Do not store the password (fixes https://github.com/owncloud/core/issues/11385)
- Refactor to AppFramework
- Add unit tests

Conflicts:
	settings/admin/controller.php

- Added setup checks in JavaScript
- Moved isWebDAVWorking to JS using SetupChecks
- Moved internet connection checks to an ajax call that goes through the
  server

Added timeout in DeleteHandler to auto-delete after a delay.

Fixed issue where OC.Notification.hide() was called twice in a row when
deleting multiple entries, causing the second notification to disappear.
Fixed issue where "undo" click event handler was registered multiple
times when calling setNotifications() twice.
Added JS unit tests for the DeleteHandler class.

Refix undo users, groups feature

Timeout is now cleared in cancel().

Fixed click handler name for "undo" to be able to work with multiple
DeleteHandler instances (in our case one for users and one for groups)
so that there is no conflict.

To avoid making a server request every time the dropdown opens, the
whole list of groups are cached (from the last request):

Whenever the user types in a search term it will still send server
requests.

Added explicit escaping.
Now internally using a pipe symbol as separator for select2, to make it
possible to use group names containing commas.