title: Git: failed to push some refs although I have done git pull
body: <p>I started to get 'failed to push some refs' error when I changed some files and tried to do push. Most instructions tell to do git pull first. I have done it and git says everything is up to date. Any idea how to solve the error? I also started getting 'no version information available' message, I don't know does that have anything to do with the error.</p>
  
  <pre><code>git push origin master
  git: /usr/local/lib/libz.so.1: no version information available (required by git)
  Enter passphrase for key '/root/.ssh/id_rsa': 
  To git@[mydomain].beanstalkapp.com:/repo-git.git
  ! [rejected]        master -&gt; master (non-fast forward)
  error: failed to push some refs to 'git@[mydomain].beanstalkapp.com:/repo-git.git'
  </code></pre>