Add key-based auth to run rsync after the backup
Add key-based auth to run rsync after the backup

Authorization prompt appears only after backuping
all containers, near half of our. If user will not
enter pass during LoginGraceTime (default value 120sec)
connection will be refused. We can solve this by running
ssh-copy-id to the remote server and then use key-based
auth to run rsync after the backup is ready to upload.

Change-Id: I2e27fd09bd5df024d92038ad3a6e6c743f1fd830
Closes-bug: 1352369

stackforge/fuel-library,stackforge/fuel-library,ddepaoli3/fuel-library-dev,huntxu/fuel-library,xarses/fuel-library,huntxu/fuel-library,eayunstack/fuel-library,stackforge/fuel-library,eayunstack/fuel-library,ddepaoli3/fuel-library-dev,eayunstack/fuel-library,eayunstack/fuel-library,xarses/fuel-library,huntxu/fuel-library,huntxu/fuel-library,xarses/fuel-library,xarses/fuel-library,huntxu/fuel-library,ddepaoli3/fuel-library-dev,ddepaoli3/fuel-library-dev,eayunstack/fuel-library,ddepaoli3/fuel-library-dev,stackforge/fuel-library