Added windows and mac support for jython
Update appdirs.py

Jython on Windows has neither `ctypes.windll` no  `_winreg`, but this can be patched using `jna`.
Update appdirs.py
Update CHANGES.rst

Updated change log for Jython support.
Put back ... in CHANGES.rst
Calculate buffer size once
Removed `u` prefix from strings to fix python 3.2 syntax error
Merge pull request #41 from cpburnz/master

Support Jython on Windows and Mac