patch applied (cabal): Bump devel version number to 1.5.6

[Duncan Coutts]

Thu Oct  9 15:33:50 PDT 2008  Duncan Coutts <duncan at haskell.org>
  * Bump devel version number to 1.5.6
  To make easier to track recent Cabal / cabal-install changes

    M ./Cabal.cabal -2 +2
    M ./Makefile -1 +1

View patch online:
http://darcs.haskell.org/cabal/_darcs/patches/20081009223350-adfee-3657e84663bf60a0aa0709f6ed62fca00a8ff836.gz