Only bypass for `^_` cookies

[ericclemmons]

The WordPress stuff is buggy at best.

We should also remove the "helpful" crap that makes Varnish complicated, and just leave the stuff that makes it useful.

Therefore, no more normalization, no more "if this URL do this, if not do this", none of that.

The only cookies that are ignorable are Urchin/GA/tracking cookies that all use the _ prefix.

[EvanK]

Closing in favor of #62