Generating setup.py

[John Wright]

Hello,

I noticed that the version argument in setup.py was out-of-date.  Since
distutils makes .egg-info files based on this version information, it
would be good to have this reflect the actual version of python-debian.
So, I've renamed setup.py to setup.py.in, replacing the version string
with a placeholder, and I'm generating setup.py in debian/rules, pulling
the version from debian/changelog.

Is everyone ok with this?

Thanks,
John