plugins:foreman_docker - Release 0.2.0

Changes to be noted:
* if docker-api is semantically versioned, it should be fine to pin it < 2.0.0 
* same for wicked
* fog dependency is removed since foreman-compute provides it and it's a dependency

builds - http://ci.theforeman.org/view/Packaging/job/packaging_build_rpm/635/
1.6.0 now?