fix collectOf on Grate Module

[syaiful6]

This close #62.

[paf31]

Does collectOf aGrateExample still type check?

[syaiful6]

@paf31 hmm, no, it have different type, if we apply collectOf to aGrateExample, it will have this type instead:

collectOfTest :: forall f a b. Functor f => (a -> Tuple b b) -> f a -> Tuple (f b) (f b)
collectOfTest = collectOf aGrateExample

[paf31]

That makes sense, thanks!

[syaiful6]

do you want me to add tests for it?

[syaiful6]

@paf31 I add test example for collectOf and revert the definition, so it use aGrateExample. This way everyone can see how this functions can be used, if you run that it will output: Tuple [8,10] [16,25]. I think it useful, as we can see it look like we have Distributive instance for Tuple (which in reality it doesn't). It was surprised me, look like there are a connection between Distributive and Closed profunctor somehow.