This is a proposed patch to doc/src/sgml/libpgtcl.sgml which documents

the libpgtcl "pg_execute" command. This was mentioned on
pgsql-interfaces on Mar 3. I am posting it here in the hope that someone
will check to see if it makes sense and is correct SGML-wise.  I did run
it through jade, but this is my first try at this sort of thing.

ljb