RFR jcheck: Miscellanous fixes

[mark.reinhold at oracle.com]

2018/3/7 12:41:13 -0800, vladimir.kozlov at oracle.com:
> Which JDK releases are covered by new changesets whitelist?

All of them.

> Should we prevent use of "duke" for user's id? Are we using it 
> intentionally?:
> 
> changeset:   47215:4ebc2e2fb97c
> user:        duke
> date:        Sat Sep 09 14:36:53 2017 +0200
> summary:     Added tag jdk-10+23 for changeset 22850b3a5524
> 
> I understand that it is hard to do it now since we have a lot of such 
> entries:
> 
> $ hg log |grep "user:        duke" ttt |wc
>      3829    7658   68922

"duke" as a changeset author has been used intentionally in certain rare
cases: For merge changesets introduced by the repository-consolidation
project, for initial repository loads, and for some build tags.  So far
"duke" as a user hasn't been abused, so I'm not sure it's worth trying
to protect it.

"duke" as a reviewer has crept in because some developers list "duke"
as a temporary reviewer when they first create a changeset comment,
and then forget to put in the actual reviewers before they push.

> Is it possible to only check on 'commit' and 'push' commands?

Do you mean locally, or on the server?

Locally, if you enable the hooks then jcheck will validate changesets
that come in via hg push, pull, or unbundle (pretxnchangegroup) or via
the commit command (pretxncommit).

Both types of hooks are enabled on our hg servers.

- Mark