[MacPorts] #16723: unify the python portgroups

[Joshua Root]

For those that don't watch -tickets:

MacPorts wrote:
> #16723: unify the python portgroups
> ------------------------------+---------------------------------------------
>  Reporter:  jmr at macports.org  |       Owner:  macports-tickets at lists.macosforge.org
>      Type:  enhancement       |      Status:  new                                  
>  Priority:  Normal            |   Milestone:  MacPorts base enhancements           
> Component:  base              |     Version:  1.7.0                                
>  Keywords:                    |        Port:                                       
> ------------------------------+---------------------------------------------
>  The current practice of having separate ports of modules for each python
>  version is awkward, and will get far worse now that python 2.6 and 3.0 are
>  being released. Here is a portgroup that should be able to replace the
>  current python25 and python24 groups, and can install for any combination
>  of the available python versions at once via variants.

Please test and suggest improvements. One I can think of off the top of
my head is the ability to suppress the variants for unsupported python
versions.

- Josh