Handle deferreds from disownServiceParent

This fixes a race condition where multiple back-to-back reconfigs might
get the state of self.builders and the service children mixed up, as
reported by André Anjos <andre.anjos@idiap.ch>.
Merge branch 'buildbot-0.8.6'

* buildbot-0.8.6:
  Handle deferreds from disownServiceParent
Merge branch 'bug2281' into buildbot-0.8.6
Minor discrepancy in Bzr step doc
Merge remote-tracking branch 'upstream/master'
Merge pull request #381 from gracinet/master

Fixed an import in the documentation for Bzr step
remove branch from Repo step's source data

Including the manifest branch name makes switching branches trigger a
clobber. Repo tool takes care of cleaning up (or failing if not
possible) the tree when switching manifest branches without clobbering
what already existed. That behavior is much more eficient and equally
correct.

Change-Id: I3371ec64408d4d11e54e98d78e080c076220eda2
Add some github names to MAINTAINERS.
Merge pull request #384 from jgonzalezmendez/sourcedata_repo_step

remove branch from Repo step's source data
Eliminate circular references between JsonResource and HelpResource
Don't use self.level in HelpResource.  'help/' in the URL doesn't trigger HelpResource.
Fix typo
Add optional flag to HttpStatusPush to pass extraparameters to the HTTP POST request.

For example, a password can be provided or other relevant meta data.
Fix typo, add comment about silent packet drop.
Update buildbot_json.py to version 1.2.

Original source:
http://src.chromium.org/viewvc/chrome/trunk/tools/commit-queue/buildbot_json.py?view=markup
Make buildbot_json.py work even if natsort.py is not available
Raise a config.ConfigErrors if no serverUrl is provided to HttpStatusPush
Stop dropping packets if HttpStatusPush.serverUrl is not set
Merge pull request #387 from maruel/add_post_param

Add optional flag to HttpStatusPush to pass extraparameters to the HTTP ...
Merge pull request #388 from maruel/update_buildbot_json

Update master/contrib/buildbot_json.py