Summary:
I want to use this to warn user if he specifies reviewers that are away.
We can also implement a general query method but I think that this usage is the
most useful not only for me but also in general case.
Test Plan:
Call the method for user which is away and which is not away.
Add user status through Conduit.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran, epriestley
Differential Revision: https://secure.phabricator.com/D2492
2476c872ff