An interim code cleanup.

Major re-write of code yet has to be done, to circumvent
assigning of UNIT to current select and to deal better with 
offset, limit.

mysql-test/r/union.result

@@ -267,4 +267,3 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	const	PRIMARY	PRIMARY	4	const	1	
 2	UNION	t1	ref	b	b	5	const	1	Using where
 drop table t1,t2;
->>>>>>>