Form to augment flows

[countvajhula]

We've considered an aug form to "augment" the flow:

(-< _ f ...)
(-< f ... _)

But since it's unclear whether to augment on the right or the left, it didn't seem that useful as a distinct form. Upon further reflection, we could have the aug form respect the current chirality, so that:

(~> (aug f ...))

would be equivalent to

(~> (-< f ... _))

and

(~>> (aug f ...))

would be equivalent to

(~> (-< _ f ...))