Refactored web.arc

Refactored web.arc.

One of the tests is failing due to a bug in how query lists are encoded into http requests. The same bug is in the existing code, but now there is a test for it.

The change to ac.scm moves the ssl-connect function to ac.scm, where it seems to belong. If you'd rather leave ac.scm unchanged that function can be moved. Though it feels like all code dropping down to Racket/Scheme should be in one place.

Any feedback would be greatly appreciated!