[[meta title="Missing `~/.ssh/known_hosts` file causes errors from monkeysphere-ssh-proxycommand"]]

As a user, if you don't have a `~/.ssh/known_hosts` file,
`monkeysphere-ssh-proxycommand` produces some bogus output, like:

	cat: /home/foo/.ssh/known_hosts: No such file or directory

this should be fixable with a simple test.