And also move all the "top topics by period" routes to query string param.
/top/monthly => /top?period=monthly
/c/:slug/:id/l/top/monthly => /c/:slug/:id/l/top?period=monthly
/tag/:slug/l/top/daily => /tag/:slug/l/top?period=daily (new)
Refactors `TrustLevel` and moves translations from server to client
Additional changes:
* "staff" and "admin" wasn't translatable in site settings
* it replaces a concatenated string with a translation
* uses translation for trust levels in users_by_trust_level report
* adds a DB migration to rename keys of translation overrides affected by this commit
This is where they should be as far as ember is concerned. Note this is
a huge commit and we should be really careful everything continues to
work properly.