Encourage proposers to use suggestions box

There's no indication to a proposer that their suggestions will actually
be anonymised, leading some to reply in ad-hoc addenda to the proposal
instead.

This can be ameliorated with a reassuring call to action, telling the
proposer that their identity will be masked in any suggestions they add.
Show proposers' suggestions as "you" and hide face

This helps to reassure proposers that their suggestions are being
anonymised properly.
A proposer "responds" to a suggestion

It makes more sense for a proposer to respond to suggestions than to
suggest.
Merge pull request #24 from threedaymonk/anon-improvements

Anon improvements