Host revise

It may compile, but that doesn't mean it's going to actually work. But, I did outline the rest of the revision, found some shortcomings in the form contract protocol, and hopefully got things closer to fully functional.

In the spirit of continuing to keep our heads down, I haven't added any testing or anything fancy. This code is probably a disaster, but that's according to our current development plan.

(for outsiders: given that this is a feature branch, we've chosen to ignore testing for the time being and just get things working at all. We're in the middle of a very focused sprint to get things done, and we believe that things will get a lot easier once the general concept is working, even if it's not tested)