add p(glitch) option to veto times online by a specified threshold
I've added a few options to datasource.py to use p(glitch) to veto times based on a specified threshold. Duncan has tested this and can confirm it works.
Before I merge this in, I wanted to make sure that this all looks sensible. Specifically, whether you're okay with the options, and a point Duncan brought up where it may be better to define the p(glitch) channel directly rather than hardcode part of the channel name and just fill in the nickname (line 519).