Cabal patch: Add setup haddock --hoogle option

[Simon Marlow]

Neil Mitchell wrote:
>
> The attached patch adds support for the --hoogle option to the haddock 
> target.
> 
> Tested on the base package, now running:
> 
> runhaskell Setup haddock --hoogle
> 
> Gives the file base-2.0.txt which can then be fed into Hoogle properly.
> 
> Anything wrong with it? If not, can it be applied?

Applied, thanks.

Simon