title: How do I undo the command $ eval "$(docker-machine env blog)"
body: <p>I think that command redirected <code>$ docker</code> commands to the docker machine.  Now all my docker commands are giving me an error <code>FATA[0000] Couldn't read ca cert...</code> follwed by the path to the docker-machine I created.  How can I fix my shell? </p>