Heads up: Python & PostgreSQL default change

[Joerg Sonnenberger <joerg%britannica.bec.de@localhost>]

Hi all,
just a small note that I am about to change the default version of
Python to 2.6 and of PostgreSQL to 8.4. Especially for the latter you
should watch your updates and prepare a database dump. You can of course
still wire down the desired version (PYTHON_VERSION_DEFAULT and
PGSQL_VERSION_DEFAULT).

Joerg