Make the buildables list a little nicer.

Summary:
Depends on D7501.

This just renders the buildable's actual object name onto the list, so you can see at a glance what the buildable represents. I'd like to also pull across a list of builds of this buildable and change the bar color, but I'm not quite sure how to do that in the search architecture without N+1 querying.

Test Plan:
Looked at the buildable list and it looked like this:

{F78555}

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley

CC: Korvin, epriestley, aran

Maniphest Tasks: T1049

Differential Revision: https://secure.phabricator.com/D7502