Remove all remnants of python <2.7

[Ryan Schmidt]

On May 4, 2018, at 08:05, Perry E. Metzger wrote:

> Yesterday, Ryan pointed out in the course of a pull request that the
> port in question still had support for python 2.5(!).

It needn't be a surprise that the ports (InsightToolkit*) have python 2.5 support. The ports simply offer python variants, and use the latest versions of python that were available at the time--python24 and python25. These InsightToolkit* ports have not really been updated in a very long time.

It is not a controversial idea that it would be great if the ports were updated to use a newer python instead. There is a 4-year-old ticket about that issue for these ports, but nobody has wanted to do the work so far. There are numerous open tickets about these ports, including one requesting the removal of the older versions.

python26 and later are structured differently (as a "framework" build) from python25 and earlier. This can require changes in ports beyond simply changing the python version number. There is an 8-year-old ticket open about that issue for these ports.