Build folders and scripts for creating single-file PyInstaller
executables on Windows and Linux, and a py2app app bundle (folder) 
on Mac OS X.  See each folder's build.* script for more details.

These are never required for the more portable and general
source-code distribution, but source-code scripts cannot be 
associated to open files automatically (apart from using a 
.bat file on Windows, which flashes on open).

App/exe builds also do better on icons, drag-and-drop, and
otherwise; open on clicks everywhere; do not require a Python
(or other) install; and freeze a version of Python with known
behavior to innoculate programs from future Python changes.

OTOH, they also obscure code and code-based config files too
well, and are not as portable as source.

The products of these builds are always stripped for space in
source-code packages; visit learning-python.com/programs or run
the scripts to restore the products.

NOTE: the version of Python you use to run the build scripts 
here is crucial--it's the version bundled with the app/exe.