Add "sort" options for translation view

[zekiel]

Sort by:

by Votes by Last Updated. ...etc.

[zekiel]

This will be doubly useful for TMs to review new translations in their language.

In those cases, clicking the "3 new translations" notification would send you to Translations in your language sorted by from most--> least recently updated.

[jbarrett]

On #342 I'm also implementing a "group" view for stuff that doesn't have an existing "group" page. If there are 3 new comments on a thread, you visit the thread - that's fine. There's no similar page for new tokens (well, there is, but it's not practical to use for this purpose) or translations.

What we can do here is have, say, a generic event template so you can link any notification to its event id on duck.co/event/2138 and it will include the templates for the objects in that event, so if the event contains references to a set of translations, they'll be shown in date order.

The event and template infrastructure should allow for this without too much work.