Dashboard: Display localized time strings for updates

Closes #606 (closed)

What does this MR do?

Removes the previously used jQuery plugin timeago and instead uses utils::dateDistanceInWords to display passed time since an update was posted. Since dateDistanceInWords is localized, date strings on the Dashboard will now be displayed in German.

How confident are you it won't break things if deployed?

Rather confident.

Links to related issues

Any relevant links (issues, documentation, slack discussions).

How to test

Steps a reviewer can take to verify that this MR does what it says it does e.g.

1. Checkout branch locally
2. Login as foodsaver
3. Go to Dashboard
4. Check time strings underneatch each update: Are they displayed correctly?

Screenshots (if applicable)

Checklist

• added a test, or explain why one is not needed/possible...
• no unrelated changes
• asked someone for a code review
• joined #foodsharing-beta channel at https://slackin.yunity.org
• added an entry to CHANGELOG.md (description, merge request link, username(s))
• Once your MR has been merged, you are responsible to update the #foodsharing-beta Slack channel about what has been changed here. They will test your work in different browsers, roles or other settings