title: Gevent is in an unsupported or invalid wheel
body: <p>I try on my osX (el capitan) to install Odoo.
  Then i've download the package and when I try to install the 3rf party lib with <code>pip install -r requirements.txt</code>, it gives me:</p>
  
  <pre><code>gevent is in an unsupported or invalid wheel
  </code></pre>
  
  <p>Any idea ?
  Xcode is installed, the command line tools too.</p>