patch applied (cabal-install): Add lookupConfiguredPackage helper function to InstallPlan

[Duncan Coutts]

Tue May  6 17:10:06 PDT 2008  Duncan Coutts <duncan at haskell.org>
  * Add lookupConfiguredPackage helper function to InstallPlan
  Simplifies implementation of completed and failed

    M ./Hackage/InstallPlan.hs -4 +13

View patch online:
http://darcs.haskell.org/cabal-install/_darcs/patches/20080507001006-adfee-2aff7725eaf0e06c489eceaadf93b92ab6392d35.gz