title: Limit Read and Write Access to branches of a plain git repository based on user name
body: <p>We are building an assessment process and want to limit the read and write access to specific branches for special users.</p>
  
  <p>there are "normal" users that have read and write access to everything (these users will rate the answers) and there will be a given number of assessment users that should only have read access to master and read/write access to branches that contain their names (e.g. <code>assessment-john.doe</code>). Our assessment center will have a list with 500 users and passwords and will give each candidate a set of credentials from this list.</p>
  
  <p>Short version: I'd like to configure git, that:</p>
  
  <ul>
  <li>Normal Users (e.g. <code>tobi</code>, <code>chris</code>) have:
  
  <ul>
  <li>read &amp; write access to master</li>
  <li>(ideally only) read access to branches starting with <code>assessment-</code></li>
  </ul></li>
  <li>Assessment Users (e.g. <code>assessment-1</code>, <code>assessment-2</code>) have:
  
  <ul>
  <li>read access to master</li>
  <li>read/write access to branches that have the same
  name as the user (e.g. <code>assessment-1</code>)</li>
  <li>no access to other branches.</li>
  </ul></li>
  </ul>
  
  <p>We want to use plain git (and ssh) without any version control gui server like gitlab or github as the task doesnt require this.</p>
  
  <p><strong>EDIT</strong>: To make it clear: Read control is way more important that write control. (except for master).</p>