Update deasync.

See #110 (closed) and #115 (closed).

I'm running a project from my fork, but haven't actually done any DB stuff in it yet - can't tell you if this breaks everything horribly or not. I tried running the tests in my fork with iojs 3.3.0 and they all failed. But then I tried running the tests with the latest pre-4.0 node version the other day and they all failed with that too. I feel like I'm Doing It Wrong™, that somebody would have noticed if all the tests were failing.

Anyway, I can confirm that the latest version of deasync builds just fine with the new 4.0.0 release of node and iojs 3.3.0.