Fixes "This app has no minimum ownCloud version assigned. This will be an error in ownCloud 11 and later.", the tag can only be there once. Also set to 9.0 as this will be the next major release.
For admins: display the namespace behind the tag name.
For users: no namespace, don't display non-assignable tags in the
dropdown, display already assigned non-assignable tags with a different
style
Joas Schilling
Lukas Reschke
Vincent Petry