unneeded configure work.

configuration.

calls with new or now-built-in versions.  Make sure that all
calls to AC_DEFINE have a third argument, for possible use of
autoheader in the future.

choice of compiler and flags, uninstall, and peculiar Python installation
layouts for PyGreSql.  Also install into site-packages now, as officially
recommended.  And pgdb.py is also installed now, used to be forgotten.

there's no shared libpython.  Test suite works as well. Also, add some
documentation.

that now functions as a wrapper around the MakeMaker stuff. It might
even behave sensically when we have separate build dirs. Same for plperl,
which of course still doesn't work very well. Made sure that plperl
respects the choice of --libdir.

Added --with-python to automatically build and install the Python interface.
Works similarly to the Perl5 stuff.

Moved the burden of the distclean targets lower down into the source tree.
Eventually, each make file should have its own.

Added automatic remaking of makefiles and configure. Currently only for the
top-level because of a bug(?) in Autoconf. Use GNU `missing' to work around
missing autoconf and aclocal. Start factoring out macros into their own
config/*.m4 files to increase readability and organization.