title: how to add ssh public key to a specific git repo
body: <p>I have a git repo, i connect via root to push and pull. I have another user i'd like to have access to my repo. </p>
  
  <p>I have got him to create me a public key file for me to add to my servers <code>~/.ssh/authorized_keys</code></p>
  
  <p>How do i then restrict him from having access to my entire server?</p>