patch applied (cabal): Add PackageIndex.insert and reverse merge/mappend

[Duncan Coutts]

Tue Apr 15 13:36:37 PDT 2008  Duncan Coutts <duncan at haskell.org>
  * Add PackageIndex.insert and reverse merge/mappend
  Packages in the second argument to merge now mask those in the first.

    M ./Distribution/Simple/PackageIndex.hs -9 +22

View patch online:
http://darcs.haskell.org/cabal/_darcs/patches/20080415203637-adfee-1ad59c6ebc462a24d691a75bac2533dd2a50d248.gz