Use optparse for the pip2pi, dir2pi, and pip2tgz commands.
Add --symlink and --no-symlink.

I need to create a local PyPI on Mac and Linux machines,
which will be checked into Git, then used on Windows machines.
Msysgit doesn't support symlinks, so I have to copy files into
PACKAGE_DIR/simple/. Since the copy resolves to the same file object,
as they have identical hashes, no space is wasted in Git.
Ignore unrecognized options so that they can be passed to pip
Use Py3K-compatible exception-handling syntax
s/UseSymlink/OS_HAS_SYMLINK/