Use fixedresolver.py from dnslib in chutney

Tor Exits in chuntey run DNS checks to external addresses. This is one of the things stopping chutney from working when there is no DNS.

We could redirect DNS queries to fixedresolver.py from Python's dnslib, and that would make sure DNS would all run locally.

(Although we might have to reply with a few different addresses somehow, because tor gets suspicious if every address from DNS is the same.)