errors.  Include Python version in setuptools' egg name for compatibility
w/installs via easy_install.  Add isdir/listdir facilities for metadata,
along with support for running scripts from eggs.

--HG--
branch : setuptools
extra : convert_revision : svn%3A6015fed2-1504-0410-9fe1-9d1591cc4771/sandbox/trunk/setuptools%4041053