pgsql: Fix up hack to suppress escape_string_warning so that it actually

Log Message:
-----------
Fix up hack to suppress escape_string_warning so that it actually works
and there's only one place that's a kluge, ie, appendStringLiteralConn.
Note that pg_dump itself doesn't use appendStringLiteralConn, so its
behavior is not affected; only the other utility programs care.

Modified Files:
--------------
pgsql/src/bin/pg_dump:
dumputils.c (r1.29 -> r1.30)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_dump/dumputils.c.diff?r1=1.29&r2=1.30)
pgsql/src/bin/psql:
command.c (r1.167 -> r1.168)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/command.c.diff?r1=1.167&r2=1.168)
common.h (r1.48 -> r1.49)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/common.h.diff?r1=1.48&r2=1.49)
copy.c (r1.62 -> r1.63)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/copy.c.diff?r1=1.62&r2=1.63)
describe.c (r1.138 -> r1.139)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/describe.c.diff?r1=1.138&r2=1.139)
pgsql/src/bin/scripts:
createdb.c (r1.20 -> r1.21)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/scripts/createdb.c.diff?r1=1.20&r2=1.21)
createuser.c (r1.31 -> r1.32)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/scripts/createuser.c.diff?r1=1.31&r2=1.32)