CREATE OR REPLACE FUNCTION

Hi guys,

Here's a patch I put together. I thought the Oracle-style 'CREATE OR
REPLACE FUNCTION' syntax might be useful to those doing lots of function
creation/development. It is against the 7.1.3 source.

I ran it through regress - all tests were fine. I also modified the
regress to use the potential OR REPLACE syntax. This also worked.

Gavin