New version of site.py hack, for better compatibility with distros that

patch the stdlib site.py.  This version runs the stdlib site.py, then
tries to hack sys.path back to something resembling what the old version
did.  Unfortunately, this is complex since site.py and .pth files can
munge the path in rather arbitrary ways, and the initial setup of
sys.path is dependent on the platform and Python version.  This code has
been tested on Linux, cygwin, and Windows Python, versions 2.2, 2.3, and
2.4 (although not all versions on all platforms), and appears to perform
as intended.

--HG--
branch : setuptools
extra : convert_revision : svn%3A6015fed2-1504-0410-9fe1-9d1591cc4771/sandbox/trunk/setuptools%4042302