Merge pull request #12 from saketoba/support-openstack-network-name

support get_ip from user-defined network group
Merge pull request #11 from saketoba/use-ssh_key

Care about ssh_key option
Update CHANGELOG, bump version for release
Bump version for dev
Merge branch 'master' of git://github.com/RoboticCheese/kitchen-openstack into dev
fix wait_for_sshd args