Add SSH Action

 * We need an another way to communicate with VM,
   so SSH is this way. Also it gives a possibility
   to check if VM operation system is up by sending
   a simple ssh command to it.
 * Added SSH Action
 * Only password access, forwarding public/private keys
   will be in the future
 * It is tested on real VM. However, it needs to be tested
   by somebody else

Implements blueprint mistral-ssh-action

Change-Id: I7c51453afb6a926bbce01f4a9065a3c313a79fff