Clarify the difference between Traversable and Traversable1

[hdgarrood]

...which is that Traversable1 is a stronger requirement, since it only requires Apply constraints on the type variable f, as opposed to Applicative. I think we should also try to come up with a convincing example of this class. What interesting Apply instances are there which are not Applicative? https://blog.functorial.com/posts/2015-12-06-Counterexamples.html lists Const k where k is a semigroup but not a monoid, and also Map k.