haskell port group

[Bryan Blackburn]

FYI, for those interested, I just added a port group for haskell [1], which
currently supports only ghc (which seems okay since the other hs-* ports I
checked are all ghc-specific).  It does the standard 'runhaskell Setup...'
routine.

I also updated three ports to use it, so you can use them as examples:

<http://trac.macports.org/browser/trunk/dports/devel/hs-digest/Portfile>
<http://trac.macports.org/browser/trunk/dports/devel/hs-utf8-string/Portfile>
<http://trac.macports.org/browser/trunk/dports/devel/hs-zip-archive/Portfile>

Bryan

[1] - <http://trac.macports.org/changeset/45388>