---------------------------------------------
	Make type synonyms uniform with data types
	so far as infix operators are concerned
	---------------------------------------------

	Merge to STABLE


This allows

	type (a :+: b) c d = ...

which was prevented before by accident.

I've also documented the fact that classes can be infix;
and arranged that class constraints in types can be in infix form.
	f :: (a :=: b) => ....