hg: code-tools/jcheck: Add a hook to check pushkeys

[john.coomes at oracle.com]

Changeset: 5cc7a44300dd
Author:    jcoomes
Date:      2014-03-11 14:29 -0700
URL:       http://hg.openjdk.java.net/code-tools/jcheck/rev/5cc7a44300dd

Add a hook to check pushkeys

Add a server-side prepushkey hook to disable pushing keys, except for phases
data.  Bookmarks (e.g, '@') can become stale when old hg versions are used on
the client, leading to surprising behavior.

! jcheck.py