Make it more clear that red dots next to usernames mean Calendar availability

Summary:
Ref T11809. We show a red dot next to a username to indicate that the user is away (on vacation, in a meeting, etc).

It's not very obvious what this means unless you know that's what it is: when you click the username or view a hovercard, there's no visual hint about what the red dot means. It does say "Away", but there is a lot of information and it doesn't visually connect the two.

Connect the two visually by putting a red dot next to the "Away" bit, too.

Test Plan:
Here's my version of it, this feels OK to me but could maybe be more designed:

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T11809

Differential Revision: https://secure.phabricator.com/D16791