title: Gitlab setup, rake fails because no --global user.name
body: <p>Following the 5.1 instructions to install gitlab</p>
  
  <p><a href="https://github.com/gitlabhq/gitlabhq/blob/master/doc/install/installation.md" rel="nofollow">https://github.com/gitlabhq/gitlabhq/blob/master/doc/install/installation.md</a></p>
  
  <p>When I run the command to test the install, I get an error "Git configured for user? ... no"</p>
  
  <pre><code>root@gitlab:/home/git/gitlab# sudo -u git -H bundle exec rake gitlab:check RAILS_ENV=production
  Checking Environment ...
  
  Git configured for git user? ... no
    Try fixing it:
    sudo -u git -H git config --global user.name  "GitLab"
    sudo -u git -H git config --global user.email "gitlab@gitlab.ac"
    For more information see:
    doc/install/installation.md in section "GitLab"
    Please fix the error above and rerun the checks.
  Has python2? ... yes
  python2 is supported version? ... yes
  </code></pre>
  
  <p>At no point in the instructions does it say to setup a user.name and user.email for the git user. 
  Can I safely ignore this warning, or should I deviate from the instructions and set it? </p>