Change oddly-chosen OID allocation.

I noticed while fooling with John Naylor's bootstrap-data patch that we had
one high-numbered manually assigned OID, 8888, which evidently came from a
submission that the committer didn't bother to bring into line with usual
OID allocation practices before committing.  That's a bad idea, because it
creates a hazard for other patches that may be temporarily using high OID
numbers.  Change it to something more in line with what we usually do.

This evidently dates to commit abb173392.  It's too late to change it
in released branches, but we can fix it in HEAD.

src/include/catalog/catversion.h

@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	201803211
+#define CATALOG_VERSION_NO	201803212
 
 #endif

src/include/catalog/pg_proc.h

@@ -2427,7 +2427,7 @@ DESCR("exponentiation");
 DATA(insert OID = 2169 ( power					PGNSP PGUID 12 1 0 0 0 f f f t f i s 2 0 1700 "1700 1700" _null_ _null_ _null_ _null_ _null_	numeric_power _null_ _null_ _null_ ));
 DESCR("exponentiation");
 DATA(insert OID = 1739 ( numeric_power			PGNSP PGUID 12 1 0 0 0 f f f t f i s 2 0 1700 "1700 1700" _null_ _null_ _null_ _null_ _null_	numeric_power _null_ _null_ _null_ ));
-DATA(insert OID = 8888 ( scale					PGNSP PGUID 12 1 0 0 0 f f f t f i s 1 0 23 "1700" _null_ _null_ _null_ _null_ _null_ numeric_scale _null_ _null_ _null_ ));
+DATA(insert OID = 3281 ( scale					PGNSP PGUID 12 1 0 0 0 f f f t f i s 1 0 23 "1700" _null_ _null_ _null_ _null_ _null_ numeric_scale _null_ _null_ _null_ ));
 DESCR("number of decimal digits in the fractional part");
 DATA(insert OID = 1740 ( numeric				PGNSP PGUID 12 1 0 0 0 f f f t f i s 1 0 1700 "23" _null_ _null_ _null_ _null_ _null_ int4_numeric _null_ _null_ _null_ ));
 DESCR("convert int4 to numeric");