Each localized function call of the timeago calls gettext 28! times.
Even though gettext is rather fast, this escalates pretty quickly. We
effectively memoize the locales, which results in a maximum of 28
function calls in total. For pages with normal data, less calls (< 10)
are much more realistic.

Apparently the `.js-timeago-render` class serves no real purpose. All
functions that used it, directly pass a list of elements. Only one Vue
component had an (unnecessary) reference to the class. No styles are
applied.

Adds `newDate` helper to copy date object without keeping reference.
Adds negative length support in `getTimeframeWindowFrom` to go
back in time.

Formats the file to match Prettier rules
Removes all blacklisted ESLint rules

Adds methods from `app/assets/javascripts/lib/utils/pretty_time.js`
and deletes the file

Adds methods from `app/assets/javascripts/lib/utils/datefix.js`
and deletes the files

This didn't actually do anything.

MR: !12468

Let the backend do the translation.