first pass at new yum distributor migration
added clearing of orphaned parent publish directories; added docstrings
initial start on unit tests for migration script
unit tests and some bug fixes
refactored tests due to re-importing migration module does not load new module from disk
using get_collection directly
circumventing managers publish to avoid having to dynamically load all plugins
added reading of new distributor conf
Update the plugins' cancels methods for the new platform API, which doesn't pass any args.
added removal of legacy root publish directories
Merge pull request #425 from pulp/jconnor-yum-distributor-migration

Jconnor yum distributor migration
1034978 - Move to standard formatter for unit copy & remove extension
Clean up test cases
adding 2.3.1 release notes
Automatic commit of package [pulp-rpm] release [2.3.1-1].
Merge (-s ours) pulp-2.3 => master, post-build
Merge branch 'mhrivnak-231-release-notes'
Merge branch 'master' of github.com:pulp/pulp_rpm
921743 - Adjust ownership and permissions for a variety of the RPM paths.
Rename a logger to _logger.