Add the necessary .jcheck/conf file for openjdk6 repositories.

This file is consulted by the Mercurial extension jcheck, the existence of this file will trigger the jcheck hooks that a user should have configured in their ~/.hgrc file as follows:

[extensions]
jcheck=/USER_PATH/jcheck.py
hgext.hgk =
[hooks]
pretxnchangegroup = python:jcheck.hook
pretxncommit = python:jcheck.hook

The jcheck extension via these hooks will verify that the changesets created (hg commit) and those that are pulled in (hg pull) follow the basic jcheck rules for jdk6. Every user will need his own copy of the jcheck extension, which will be made publicly available soon.

If a user creates changesets without using jcheck, they just delay the checks until the push to the hg.openjdk.java.net repositories happens, where the checks will be made and your push will fail. The hg.openjdk.java.net repositories will not allow changesets in that violate the jcheck rules.

The rules are:
  * The author of the changeset must be a valid OpenJDK user (agrees to privacy and SCA)
  * Certain checks may be done on the actual code changes or names of files or legal notices,
      This serves as police agent on any rules established for the project with regards to sources.
  * The changeset comment should have the form:
NNNNNNN: Synopsis
Summary: ...
Reviewed-by: name
Contributed-by: ...
      The Summary and Contributed-by lines are optional.
      One line for each, any length.
      The NNNNNNN: Synopsis line can be repeated if a changeset fixes multiple bugs.
      The NNNNNNN numbers are bugids in the current bugtracking system for jdk6, currently bugtraq, but this will change.
      The NNNNNNN numbers cannot have been used in any prior changeset, it must be a unique bugid for a repository. The same NNNNNNN bugid can be used in several repositories of the forest, when that makes sense.
      The Synopsis line should be the same one in the bug report but does not have to be. Certain characters may cause problems and it may be necessary to have slight variations in this line. Characters that might cause issues are: []{}????
      Spaces and positions of the ':' character can be significant, get it right.
      The author and the Reviewed-by names must be different, and must be valid OpenJDK project names.
      The Reviewed-by line can contain multiple reviewers, one is required, additional ones can be added using a comma and space to separate the names, e.g. "name1, name2"
      The Contributed-by information can be anything.