Proposal: add liftA4 and liftA5 to match liftM4 and liftM5

[Henning Thielemann]

On Thu, 6 Nov 2014, Michael Snoyman wrote:

> David: I think the resistance you're seeing is coming from the fact that- at least in my experience- liftMN
> is not considered good, idiomatic Haskell code,

Who does not consider it good or idiomatic and why? Lifting things through 
some stages of types is a common thing in Haskell, or not?