title: Why I get Forbidden when trying to install drush on Travis CI via composer?
body: <p>This composer command fails on my Travis CI project (<a href="https://travis-ci.org/klausi/rules/jobs/23671085" rel="nofollow">example failed build</a>):</p>
  
  <pre><code>composer global require drush/drush:dev-master
  </code></pre>
  
  <p>It fails with:</p>
  
  <pre><code>The 'https://api.github.com/repos/RobLoach/Console_Table/zipball/9f80c91a9fc01a3cce71ae80ea5bd473cb0eba4c'
  URL could not be accessed: HTTP/1.1 403 Forbidden
  </code></pre>
  
  <p>although that file can be downloaded just fine.</p>
  
  <p>The <code>.travis.yml</code> file is <a href="https://github.com/klausi/rules/blob/8.x-3.x/.travis.yml" rel="nofollow">here</a></p>