Expanding Python base package

[Thomas Klausner <wiz%NetBSD.org@localhost>]

Hi!

pkgsrc has some hacks to allow the Python package to be split.

We separate out:
- py-curses
- py-expat
- py-readline
- py-sqlite3

I think it's time to revise this decision.  The dependencies are not
heavy (curses, expat, readline, sqlite3), and there is less surprise
for users if they install python and then can't use sqlite databases.

Why now, you ask? Python 3.12 removed the venerable distutils package
that we used for installing our own copies of these modules, so these
are broken for Python 3.12. And since they are shared with other
Python versions, we'd need a solution that works with 2.7 and 3.8-3.11
too. If we let the base package install them, we don't need this.

My suggested change is:

- change the 5 Python base packages to include these modules

- adapt pkgsrc so that we depend on these versions as new minimum
  versions

- remove the dependencies on the separate packages from the other
  packages

Comments?
 Thomas