Convert dns_timeout and dns_retransmit_interval configuration options to use millisec...

Convert dns_timeout and dns_retransmit_interval configuration options to use millisecond resolution.

One second resolution is too coarse for small timeouts in delay-sensitive
environments, especially when a retransmit, bypass, or another corrective
action is available and is likely to produce a positive outcome. In DNS world
specifically, most timeouts are measured in milliseconds.

This is a Measurement Factory project