Add primary key `id` to `category_featured_topics` and `topic_users`
Refactor array concatenation
Simplify avatar lookup class
Update client.nb_NO.yml

Moar translations. Also jumped back and fixed what I could find of the ones with missing double quotes.
v1 Complete translation for client.nb_NO.yml

All strings now have a first-take translation. Might have missed some due to the inconsistent use of double quotes, single quotes and no quotes (we're still good!).

I'm not entirely sure what happens when I apply edits to a still pending-for-pull patch; sorry if I goofed.
Locales: updated German locale, admin content like the admin section and flagging
Locale german: got another one
Merge pull request #1192 from cfstras/locale

Locales: updated German locale, mainly the admin section
Merge pull request #1188 from stephankaag/simplify_avatar_lookup

Simplify avatar lookup class
Merge pull request #1186 from stephankaag/add_primary_keys

Add primary key `id` to `category_featured_topics` and `topic_users`
Merge pull request #1187 from stephankaag/refactor_array_concatenation

Refactor array concatenation
Merge pull request #1189 from erlend-sh/patch-4

Update client.nb_NO.yml