Merge pull request #331 from pulp/mhrivnak-releasenotes

updating release notes
Merge branch 'pulp-2.2', pre-build.
Automatic commit of package [pulp-rpm] release [2.3.0-0.18.beta].
973678 - Return a report when ISO uploads are processed.
Create base class for file based distributors and integrate it into the ISO distributor
Automatic commit of package [pulp-rpm] release [2.3.0-0.19.beta].
Automatic commit of package [pulp-rpm] release [2.3.0-0.20.beta].
Update for comments from pull request
Update for comments from pull request
Merge pull request #354 from pulp/barnabycourt-file_distributor

Use common base FileDistributor instead of iso specific one
Merge branch 'rbarlow-973678'
Automatic commit of package [pulp-rpm] release [2.3.0-0.21.beta].
Merge branch 'master' into jconnor-new-yum-distributor
Merge branch 'jconnor-new-yum-distributor' into jconnor-publish-errata