pgsql: Fix snprintf to handle %$ properly by storing and reordering the

Log Message:
-----------
Fix snprintf to handle %$ properly by storing and reordering the
arguments.

Nicolai Tufar

Modified Files:
--------------
pgsql/src/port:
snprintf.c (r1.19 -> r1.20)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/port/snprintf.c.diff?r1=1.19&r2=1.20)