fairly tight control, and the '_setup_stop_after' and '_setup_distribution'
globals to provide the tight control.
This isn't entirely reliable yet: it dies horribly with a NameError on the
example PIL setup script in examples/pil_setup.py (at least with Python
1.5.2; untested with current Python). There's some strangeness going
on with execfile(), but I don't understand it and don't have time
to track it down right now.
Changed 'core.setup()' so it sets them to reasonable defaults.
Tweaked how the "usage" string is generated: 'core' now provides
'gen_usage()', which is used instead of 'USAGE'.
Modified "build_py" and "sdist" commands to refer to
'self.distribution.script_name' rather than 'sys.argv[0]'.
the Command class from core.py to cmd.py. No other code needs changing
though; distutils.core still provides the Command and Distribution classes,
although indirectly now.
Simplified 'Command.get_peer_option()' a tad -- just call 'find_peer()'
to get the peer command object.
Updated 'Command.copy_file()' to take a 'link' parameter, just like
'util.copy_file()' does now.
Added 'Command.make_archive()' to wrap 'util.make_archive()'.
Fix 'Command.set_undefined_option()' to call 'ensure_ready()' rather
than 'finalize_options()' (which is only supposed to be called once,
which is the whole point of 'ensure_ready()').
Added comment to 'set_peer_option()' to remind myself that this method
cannot work and is fundamentally wrong-headed.
