Error handling in TwistedResolver

I'm testing Motor with Tornado 3's Resolver, and noticed that TwistedResolver doesn't handle errors. resolve() never executes its callback / resolves its Future, and when the Deferred is deleted it logs:
```
Unhandled error in Deferred:
Unhandled Error
Traceback (most recent call last):
Failure: twisted.names.error.DNSNameError: <twisted.names.dns.Message instance at 0x101958d40>
```