Re: Monad of no `return` Proposal (MRP): Moving `return` out of `Monad`

I propse to remove the "Legacy" designation (see below for reasoning). There should probably also be some reference to the Applicative type class, so I'd propose a wording more like:

Alias for 'pure' in the 'Applicative' type class.

Reasoning: I happen to rather like "return" for purely pedagogical purposes since it lets you pretend (as a sufficient-for-beginners approximation) that code in the do-notation in IO is imperative code and "return" is the usual name for what it does in that context. I think that has a certain value, but "Legacy" is quite off-putting.

+1 "Legacy" suggests that there is a plan to remove `return` at some point. -- Michael Walker (http://www.barrucadu.co.uk)