Add optional moderator codes (#2413)

* add column for moderator code

* add interface for moderator access code

* add support for write and update moderator access

* check if correct moderator_code in session

* move access code form into own component

* add support for moderator access code

* add support for moderator access code

* add copy code button for moderator code

* freeze all the things

* add tests for moderator access code

* add helpfer for moderator_access setting

* add setting for moderator access code

* show setting for moderator access code

* add checks for moderator code setting

* use method from room controller for moderator password check

* add tests for login with moderator access code

* add check for moderator code setting

* check if moderator codes are enabled in settings

* only display form for moderator code if enabled in settings

* add newline at end of file

* make check for moderator code available as helper

* align style of join button and access code button

* add localization for moderator codes

* add field for moderator codes

* add field for moderator access code to rooms

* fixes for rubocop

* fix LineLenghts for rubocop

* fix double space

Co-authored-by: Ahmad Farhat <ahmad.af.farhat@gmail.com>