Bring more proposal 220 sections in sync with implementation
Update proposal 228 to reflect implementation status
Update proposal 220 voting process to be actually secure

This makes it mirror the existing voting process, and ensures that
the results are equivalent once everybody is updated.
Merge branch '220_evolution'

This branch reflects changes I've needed to make in proposals 220 and
228 to reflect what's sensible or implementable (as far as I've found
while implementing them).