[PythonCAD] Update for preference storing on Windows

[Art Haas]

Hi.

I've commited a patch which stores user preferences in the
${APPDATA}/PythonCAD/prefs.py path on Windows. The 'APPDATA' environment
variable provides the path to store program files in, and storing the
files in a 'PythonCAD' as opposed to '.pythoncad' directory is more
consistent. This change is available via 'svn update'. This change, btw,
should not affect Unix/Linux users.

Art
-- 
Man once surrendering his reason, has no remaining guard against absurdities
the most monstrous, and like a ship without rudder, is the sport of every wind.

-Thomas Jefferson to James Smith, 1822