title: Python source files not extracted when I pip install my package
body: <p>I've created some small and simple python package and uploaded it to the PYPI.<br>
  When I install my package using pip install, everything works fine,<br>
  but the python source files are not extracted, the installed-files.txt file does not   include it.<br>
  SOURCES.txt DOES include the python source file.<br>
  Only __init__.py file is extracted.  </p>
  
  <p>I can not understand what is wrong with my package or the way I create it.<br>
  Please advice....  </p>
  
  <p>My package name is <strong>test_pypi</strong><br>
  You can find it here: <a href="https://pypi.python.org/pypi/test_pypi" rel="nofollow">https://pypi.python.org/pypi/test_pypi</a><br>
  Package has no requirements  </p>
  
  <p>Package folder contains following files:  </p>
  
  <ul>
  <li><p>__init__.py - empty file </p></li>
  <li><p>LICENSE.txt - contains Apache license  </p></li>
  <li><p>MANIFEST.in  </p>
  
  <pre><code>include READMT.rst  
  include LICENSE.txt  
  recursive-include test_pypi/mdl *.py
  </code></pre></li>
  <li><p>setup.py  </p>
  
  <pre><code>from setuptools import setup
  
  def readme():
  with open('README.rst') as f:
          return f.read()
  
  setup(name='test_pypi',
      version='1.0',
      description='test_pypi_description',
      url='https://pypi.python.org/pypi/test_pypi',
      license='LICENSE.txt',
      author='Evgeny Fedoruk',
      author_email='minievg@hotmail.com',
      packages=['test_pypi'],
      install_requires=[],
      zip_safe=False)  
  </code></pre></li>
  </ul>
  
  <p>The package folder (test_pypi) contains:  </p>
  
  <ul>
  <li><p>__init__.py - empty file  </p></li>
  <li><p>mdl (folder) contains  </p>
  
  <ul>
  <li><p>empty __init__.py file  </p></li>
  <li><p>python source file <em>test.py</em>  </p>
  
  <pre><code>print 'hello'
  </code></pre></li>
  </ul></li>
  </ul>
  
  <p>I do the following for uploading the package:  </p>
  
  <pre><code>python setup.py register sdist upload
  </code></pre>
  
  <p>I do the following for installing it:  </p>
  
  <pre><code>pip install test_pypi
  </code></pre>
  
  <p>One last thing, I tried installing it with virtual env and without it - same problem, the <em>test.py</em> file is not extracted  </p>