Merge branch 'master', remote-tracking branch 'remotes/upstream/master'

* remotes/upstream/master:
  provide "xxx joined yyy" notifications
  adding META viewport tag for better look on tablets
  Update Esperanto to 100%
  DE update to the strings
  activitystreams schema constants for "join group"
  missed a db field
  typo in profile_selectors, fix remote tagging
  not all profile selector choices have unique or direct translations
  log db error strings in all cases
  admin page to manage failed updates
  improved db error logging
  close one menu (like the notifications menu) when another one is opened (like it is done when clicking somewhere else) (thx to ^mw)

* master: