if a port needs 2.x then set MODPY_VERSION=${MODPY_DEFAULT_VERSION_2}.
This commit doesn't change any versions currently used; it may be that
some ports have MODPY_DEFAULT_VERSION_2 but don't require it, those
should be cleaned up in the course of updating ports where possible.
Python module ports providing py3-* packages should still use
FLAVOR=python3 so that we don't have a mixture of dependencies some
using ${MODPY_FLAVOR} and others not.
slight tweaks from me) who takes maintainer
N.B. config and feed db are not compatible with the previous version,
run "r2e list > ~/r2e.txt" and "r2e opmlexport > ~/r2e.opml" to keep plain
copies of these before updating, and follow pkg-readme after updating.
