Adding an ignore function to Control.Monad

[Don Stewart]

gwern0:
> OK, let's apply a little democracy here. Reading back through the
> thread, I tally the votes:
> 
> # Nothing
> David Menendez
> John Meachem (?)
> 
> # Just
> ## Control.Monad.ignore m a -> m ()
> Michael Snoyman
> Neil Mitchell
> Isaac Dupree
> Maurí­cio
> Martijn van Steenbergen
> 
> ### Control.Monad.ignore f a -> f ()
> Edward Kmett
> 
> ## Control.Monad.void m a -> m ()
> Don Stewart
> Iavor Diatchki


That's an odd mix too. I wonder if we even reached quorum.

-- Don