[webui] Adapt search controller test
[dist] update gems
[backend] fix worker crash on kill_job
[backend] do not delete the missingpackages flag if we just update single packages
[backend] auto-retry package get if we have missing packages
[backend] fix indenting
[dist] update release notes
[backend] document asynchronus scheduler mode
[backend] do not error out on incomplete constraints data
[dist] add a note about new user management webui
[backend] dispatches: let an empty method spec match all methods, not just GET/HEAD/POST

Leaving out the "method:" part still only matches GET/HEAD/POST.
[api] speeding up the request search from timeout to < 1 second when having 30 requests with multiple actions and reviews.

The "SELECT DISTINCT" got dropped by activerecord before on exection. Even though
it claimed to use when debugging with .to_sql. Dunno how to create a test case for
this without grepping over the logfile.
[webui] display all users, sign-up form only in non-proxy mode
[webui] Add tokeninput gem for group adding and editing