hgbuildbot.py produces changes with bogus repository strings

[dustin]

It's stripping components from the left of the string, so that the result is a right-aligned substring of the full URL. This should, instead, be the full URL.

Also, the meaning of 'repository' and 'project' should be *much* more clearly documented.

[dustin]

The hgbuildbot-specific part of this was fixed in

commit 8dffe34236deefc850abb7fb5cfc6be56717d6b9
Author: Dustin J. Mitchell <dustin@mozilla.com>
Date:   Sat Feb 4 13:51:02 2012 -0600

    use hgbuildbot.baseurl, not ui.baseurl, to construct repositories
    
    Also merge documentation for the Mercurial Hook into the manual.

commit 757f0dad8a0956f440360f236e8d03feae78d880
Merge: 49d09ba e00977a
Author: Dustin J. Mitchell <dustin@mozilla.com>
Date:   Sat Feb 4 13:24:20 2012 -0600

    Merge branch 'fix_hgbuildbot' of git://github.com/hborkhuis/buildbot
    
    * 'fix_hgbuildbot' of git://github.com/hborkhuis/buildbot:
      Revert "proposal for include_baseurl"
      release note for hgmercurial bugfix
      proposal for include_baseurl
      hgbuildbot returns complete url as repository

Documenting repository and project clearly remains to be done.

[Dustin J. Mitchell]

Document the meaning of 'project' and 'repository'

Fixes #2184.

Changeset: 6d822f2dbda5a15b329e329edc071665af3cc806