Don't fatal on daemon status updates from phd

Summary:
See D3126, T1667, T1658. Prior to D3126, phd did not use MySQL directly. Now that it does, there are at least two specific problems (see inline comment).

In the long term, we should probably break this dependency and use Conduit. However, we don't currently have access to the daemon log ID and getting it is a mess (the overseer generates it), and I think I want to rewrite how all this works at some point anyway (the daemon calls are currently completely unauthenticated, which is silly -- we should move them to an authenticated channel at some point, I think).

Test Plan: Ran phd stop with a bad MySQL config against a non-running daemon, didn't get a query error.

Reviewers: nh, vrana, btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T1667, T1658

Differential Revision: https://secure.phabricator.com/D3314