Mail address of users is now changable in the user management

Wording fixes for sharing dialog

Returns tags through WebDAV

Wave accessibility compliance

Add Redis cache implementation, prefer over memcached, tests & config sample doc

Add a isLoggedIn method to the usersession and deprecate the isLoggedIn ...

Add mount specific options

make sure styles and scripts are only loaded once

first step to drop \OCP\Config:: in favour of IConfig

* 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

Send mail for new users

show spinner on file upload in IE8, 9

HHVM: Do not call filesize(null), this function expects a string.

filesize(null) yields an int on HHVM and thus exif_imagetype(null) is called.

Fix extra quotes in custom tags in header

Fix #12939

Fix deleting invalid s2s shares

be more explicit in JS unit tests - caused by accessibility issues

fix initial loading limit of user management on large screens

Move the Null-Byte LDAP check to the user manager

HHVM: Add workaround for missing Memcached::deleteMulti()