title: How to tell py.test to skip certain directories?
body: <p>I tried to use the <a href="http://pytest.org/latest/customize.html#confval-norecursedirs" rel="noreferrer"><code>norecursedirs</code></a> option inside setup.cfg to tell py.test not to collect tests from certain directories but it seems it does ignore it.</p>
  
  <pre><code>[tool:pytest]
  norecursedirs=lib/third
  </code></pre>
  
  <p>When I run <code>py.test</code> I do see how it does get tests from inside <code>lib/third</code>!</p>