Highlight away and sporadic users in revision list

Summary:
This is not so general as getRequiredHandlePHIDs().
It allows bulk loading of user statuses only in revision list.

It also loads data in render(). I'm not sure if it's OK.

Maybe we can use the colorful point here.
Or maybe some unicode symbol?

Test Plan: {F11451, size=full}

Reviewers: btrahan, epriestley

Reviewed By: btrahan

CC: aran, Koolvin

Differential Revision: https://secure.phabricator.com/D2484