Stylistic issues in the spec

[zugz]

This is just to record some general stylistic issues in the spec which bug me.
This list is undoubtedly incomplete.

• The pronoun for a peer is sometimes "him". Remind me which century this is?

• More often, it's "them", which isn't too bad, except that "themselves" is
  often used for a single peer, which is confusing. I would either use "it"
  for the peer, or use "themself".

• Tense and modality are used inconsistently - sometimes an implementation
  "will" do something, often it "does" it, and occasionally it "should" or
  "must" do it. We should decide whether this is describing the behaviour of
  current implementations, in which case present tense "does" seems best to
  me, or whether it is defining a conforming implementation, in which case use
  of "may", "should", and "must" as in RFCs would be appropriate.

• There should be a typographical convention for introducing a definition. I
  favour bold text, as in "A gostak is a distimmer of doshes".

• "group", "groupchat" and "group chat" are used interchangeably; we should
  replace them all with "conference".