ports/187091: [exp-run] allow coexistence of python ports with different python versions required (py33-foo and py27-bar)

[Sunpoet Po-Chuan Hsieh]

>Number:         187091
>Category:       ports
>Synopsis:       [exp-run] allow coexistence of python ports with different python versions required (py33-foo and py27-bar)
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-ports-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          change-request
>Submitter-Id:   current-users
>Arrival-Date:   Wed Feb 26 18:40:00 UTC 2014
>Closed-Date:
>Last-Modified:
>Originator:     Sunpoet Po-Chuan Hsieh
>Release:        FreeBSD 10.0-STABLE amd64
>Organization:
The FreeBSD Project
>Environment:
System: FreeBSD bonjour.sunpoet.net 10.0-STABLE FreeBSD 10.0-STABLE #0 r261402: Mon Feb 3 22:35:15 CST 2014 sunpoet at bonjour.sunpoet.net:/usr/obj/usr/src/sys/bonjour amd64
>Description:
setuptools (devel/py-setuptools) is used for every python ports since r336553.

Please consider the following case:
- py-foo (USE_PYTHON=3) which depends on py33-setuptools
- py-bar (USE_PYTHON=2) which depends on py27-setuptools

We could have only 1 pyXX-setuptools installed, either py33-setuptools or
py27-setuptools, due to limitation of ORIGIN. As a result, these two ports
can't be installed together.

This PR suggests the addition of devel/py-setuptools{27|31|32|33} for different
python versions. This suggestion received no objection among several python@
committers. It also avoids packaging failure for python ports requires Python
3.x (non-default python version), e.g. [1][2].

[1] http://beefy2.isc.freebsd.org/bulk/83amd64-default/2014-02-26_04h39m00s/logs/py33-dns3-3.0.4.log
[2] http://beefy2.isc.freebsd.org/bulk/83amd64-default/2014-02-26_04h39m00s/logs/py33-kyotocabinet-1.22.log
>How-To-Repeat:
>Fix:
The patch is available at http://people.FreeBSD.org/~sunpoet/py-setuptools.patch
>Release-Note:
>Audit-Trail:
>Unformatted: