python-setuptools: forkbump and add workaround for shebangs

Switch to distribute fork since it's maintained and fixes a few issues
while bumping to version 0.6.36.
There's work upstream in re-merging with setuptools which is now
supposedly maintained, see
http://mail.python.org/pipermail/distutils-sig/2013-March/020126.html



Buildroot python packages should use --single-version-externally-managed
and --root=/ in the install phase even if they're not setuptools-based.
This is because the default is to build egg files (zip files) for
packages to support multiple target versions, and since the packages
should be handled by buildroot infrastructure that's not needed.
Also potentially doing double-compression is time-wasting (i.e. egg
file and target filesystem) when running on slow targets.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>