Add setup.py file for building Windows installer

This setup.py file allows building an executable version of the
installer that doesn't require an external Python installation.
Add script for building Windows installer

This script tells Inno Setup how to build the stand alone installer
Add a Software Carpentry icon file for Windows installer
Merge branch 'inno' into namespaced-inno

* inno:
  Add a Software Carpentry icon file for Windows installer
  Add script for building Windows installer
  Add setup.py file for building Windows installer