This patch adds an 'install_egg_info' command to the
distutils install process, that writes the standard
PKG-INFO metadata to a file in the directory where the
associated modules are being installed.  The filename
is based on setuptools' conventions for reading and
writing such files, so that setuptools will be able to
recognize distutils-installed packages as being
present, and not attempt to reinstall them if they are
sufficient to meet a requested dependency.

As currently implemented, Python's main setup.py causes
a Python-2.5a0-py2.5.egg-info to be installed in
lib-dynload.  It would probably be best if it also
created similar files for ElementTree, ctypes, and any
other packages incorporated into 2.4 or 2.5 that were
separately distributed for Python 2.3.  But that
feature doesn't have to be in alpha 1.