Add an extra class to Control.Applicative.Alternative

[John Wiegley]

>>>>> Edward Kmett <ekmett at gmail.com> writes:

> Off the cuff, I'm currently -1 on this proposal, almost entirely because of
> the concern I'd have that pushing it too far up the class hierarchy actually
> invites a worse experience due to orphans than leaving it closer to the use
> site where such ambiguous cases can be resolved unilaterally by the author
> or ignored as irrelevant by them safely.

-1 in agreement with Edward.

John