new language extensions

[Manuel M T Chakravarty]

Duncan Coutts wrote:
> GHC 6.8 has a lot of new names for language extensions which are not  
> yet
> listed in Language.Haskell.Extension:
[..]
> PArr
[..]
> So I propose we add all of these to the Extension enumeration data  
> type.

I am sure we still want to change this one (maybe into  
ParallelArrays).  The feature isn't ready for prime time yet, which is  
why nobody has been paying attention to flag names.

Anyway, this is just to say, please don't bake this in yet.

Manuel