Log Message:
-----------
Add docs for a couple of formerly-undocumented geometric conversion functions.
Modified Files:
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pgsql/doc/src/sgml:
func.sgml (r1.235 -> r1.236)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/func.sgml.diff?r1=1.235&r2=1.236)