convert calls to addStep in factory.py to use instances
Merge remote-tracking branch 'origin/buildbot-0.8.8' into buildbot-0.8.8
relnotes for bug 2502
Merge branch 'buildbot-0.8.8'
Merge branch 'buildbot-0.8.8'
Merge remote-tracking branch 'org/buildbot-0.8.8' into buildbot-0.8.8
Reintroduce deprecated `workdir` property.

It is unfortunatley named, but dropping it now doesn't provide a clear
migration path. Supporting both for at least a version allows smoother
migration.
Rework locating config file for checkconfig and upgrade-master.

This changes the logic of checkconfig so that,
1. If a file is passed, that file is used.
2. If a directory is passed containing `buildbot.tac`, that file is
   loaded and `configfile` is defined there, that file is used.
3. If `buildbot.tac` doesn't exist, or doesn't define `configfile`,
   `master.cfg` from that directory is used.

The logic for upgrade-master is similar, except only directories are
supported, so (1) is skipped.
Use twisted.python.deprecate.deprecatedModuleAttribute to deprecate SetProperty.
add missing copyright header
SingleBranchScheduler: add description and note for createAbsoluteSourceStamps argument.
SingleBranchScheduler: only access database if createAbsoluteSourceStamps enabled
SingleBranchScheduler: remove shouldntBeSet argument and return None in defer
Merge branch 'shell-completions' of git://github.com/elmirjagudin/buildbot
Add delarative configuration example in master/contrib/SimpleConfig.py
Replace monkey-patching for Twisteds without completion

This just only attempts to use usage.Completion when that attribute
exists.
Merge branch 'sbs-abs-source-stamps' of git://github.com/thedylman/buildbot
remove nonexistent sourcestamp properties

Fixes #2509.
Add comments explaining use of usage.Completions
Buildslaves: add buildslave information to the database

 - new buildslaves table
 - store the (admin, host, accessURI, version) in the database