pgsql: Back out patch.

Log Message:
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Back out patch. This should be done like other server-side languages.

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This patch allows the PL/Python module to do (SRF) functions.

The patch was taken from the CVS version.

I have modified the plpython.c file and have added a test sql script for
testing the functionality. It was actually the script that was in the
8.0.3 version but have since been removed.

In order to signal the end of a set, the called python function must
simply return plpy.EndOfSet and the set would be returned.

Gerrit van Dyk

Modified Files:
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pgsql/src/pl/plpython:
plpython.c (r1.63 -> r1.64)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/pl/plpython/plpython.c.diff?r1=1.63&r2=1.64)

Removed Files:
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pgsql/src/pl/plpython/sql:
plpython_setof.sql
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/pl/plpython/sql/plpython_setof.sql)