Anonymous voting

I put up a proposal for implementing anonymous voting for the foundation elections on the wiki. This is based in part on David’s earlier proposal, but simplifies some things based on the discussion on the list and fleshes out the implementation a bit more.

It doesn’t really add to the security of the elections process (doing so would require a stronger form of authentication than “can read a particular email account”), but does anonymise the election results and lets us do things like tell the voter that their completed ballot was malformed on submission.