Fix Permissions Error

If you don't have the authorized key file readable by the SFTP group
things will break, and that permission has to be correct all the way
down. This commit took 6 hours of debugging due to a single permissions
error on /home/backups that casdcaded and drove me pretty much mad.
Because of my own simple mistake, running chmod when I meant chown early
in the debugging process, I ended up replicating this across 3 systems,
drinking more than a litre of alcohol, getting into an argument about the
NSA outside the local pub and blowing a tire on my bicycle.

This is my confession. I am an idiot.

--
Rhys