pgsql: Define snprintf() to call pg_snprintf() so our own snprintf-like

Log Message:
-----------
Define snprintf() to call pg_snprintf() so our own snprintf-like
implementation doesn't export out via libpq and get used by a user
application.

Modified Files:
--------------
pgsql:
configure (r1.432 -> r1.433)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/configure.diff?r1=1.432&r2=1.433)
configure.in (r1.405 -> r1.406)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/configure.in.diff?r1=1.405&r2=1.406)
pgsql/src/bin/pg_ctl:
pg_ctl.c (r1.54 -> r1.55)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_ctl/pg_ctl.c.diff?r1=1.54&r2=1.55)
pgsql/src/bin/psql:
command.c (r1.140 -> r1.141)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/command.c.diff?r1=1.140&r2=1.141)
pgsql/src/include:
pg_config.h.in (r1.81 -> r1.82)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/pg_config.h.in.diff?r1=1.81&r2=1.82)
port.h (r1.70 -> r1.71)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/port.h.diff?r1=1.70&r2=1.71)
pgsql/src/port:
snprintf.c (r1.16 -> r1.17)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/port/snprintf.c.diff?r1=1.16&r2=1.17)