Structure package per Harold Abnabit's blog post

There is a blog post written by Harold Abnabit that recommends
how a Python package should be structured. The blog post is
available at:

  http://blog.habnab.it/blog/2013/07/21/python-packages-and-you/

This blog post is based on another post by Jean-Paul Calderone.
Jean-Paul's post is available at:

  http://as.ynchrono.us/2007/12/filesystem-structure-of-python-project_21.html

Structure the project directory of this package according to
these two posts.
Fix bugs caused by restructuring in setup.py
Save a list of installed files during make install