automatically update cowbuilder in job
update cowbuilder in launchpad too
cowbuilder update now does keys
oracle now supplies keys and mirrors
add documentation on rosdistro
update example index url to be raw
don't create cowbuilder with backports/security/updates
fix mirror/keys, have to use env variable for ros_deb
update readme, remove old cowbuilder-create script
Merge pull request #9 from mikeferguson/auto_cowbuilder

Automate creation and updates of cowbuilders, take mirrors/keys from the rosdistro