patch applied (packages/Cabal): Do the cabal version check properly.

[Ian Lynagh]

Tue Dec  2 07:54:10 PST 2008  Duncan Coutts <duncan at haskell.org>
  * Do the cabal version check properly.
  Instead of matching on the actual expression ">= x.y" we use the
  sematic view of the version range so we can do it precisely.
  Also use foldVersionRange to simplify a couple functions.

    M ./Distribution/PackageDescription/Check.hs -31 +23

View patch online:
http://darcs.haskell.org/packages/Cabal/_darcs/patches/20081202155410-adfee-c8d9ad330f5614683ccaf86218604eef2fb34da3.gz