Minor changes for WXS configuration

Leave WiX to generate the product ID
Made installation per-machine

And tidied up some of the WiX definitions
Added configuration for Pyinstaller

This takes care of transfering name and gui-script definitions from the
setup.py. Also added configuration of name and version to the WiX
configuration script (which was renamed to disambiguate it). Makefile is
updated with calls for both configuration scripts
Ignore LICENSE.* files

They're now pulled from FSF by the Makefile and/or generated
Pull name and version from setup for WiX
Fix URL in about dialog
Windows build bug-fixes

Removed redundant stuff from the .spec configure script, fixed a missing
parenthesis in the spec template, corrected dependencies in the Makefile
for the new spec configure script, etc. etc.