Drop problematic Atlantic rule

This seems no longer applicable given Atlantic SSL changes.
Bakedal SSL works now
[CATO] Vaguely-unbreak CATO

We were only matching .com before, and CATO doesn't support TLS anymore :(
[Mindshare] Remove old domains, old downgrade rules
[Stanford] www6 slac now valid SSL
[SEC] Edgar now supports SSL

It's a shame this is under platform mixedcontent.
Anchorage still requires downgrade
[SEC] just delete old invalid rule
[Stanford] www6 is already part of big rule
Merge pull request #492 from semenko/reduce-downgrade

Reduce downgrade rules