[gentoo-python] Minimal technical demo for alternate bindir scheme

[Michał Górny]

Hello, all.

I've wrapped up a first patch to demonstrate the concept of keeping
Python scripts outta bindir.

Steps to do:

1. create /etc/env.d/NNpythonpath like:

PATH="/usr/lib64/python3.3/bin:/usr/lib64/python3.2/bin:/usr/lib64/python2.7/bin:/usr/lib64/python2.6/bin:/usr/lib64/pypy2.0/bin"

(this will be most likely done by eselect-python)

2. env-update, source /etc/profile

3. apply the attached patch to the eclasses

TADAAM!

Expect new levels of screwup. Things that definitely don't work:

1. python_scriptinto() since we install all the scripts to dedicated
location. I have no idea how to support it without forking paths like
crazy.

2. things that rely on /usr/bin path. We will need new wrappers for
that. If we really want that.

3. systems with screwed up $PATH. That is, you won't find Python stuff
if you don't have proper path in PATH :).

4. python_wrapper_setup() enforces only current impl in PATH. Remaining
impls need to be provided by caller env. If they aren't, some deps with
mis-matched impls may not work.

Enjoy, test and comment.

-- 
Best regards,
Michał Górny