Add more verification, and use ssh rather than keyscan
Add more verification, and use ssh rather than keyscan

While the hostname is supposed to be correct (since that's
only for authorized users, and with git), I prefer to be extra
cautious and check arguments passed to shell. I also found out
that pipe redirection would likely not work, so I had
to find a work around using ssh (no need for real connect however,
so that's why I do not care about the username).

mscherer/ansible-role-ansible_bastion,OSAS/ansible-role-ansible_bastion,OSAS/ansible-role-ansible_bastion,mscherer/ansible-role-ansible_bastion