patch applied (cabal): Try and simplify cleaning by always removing dist

[Duncan Coutts]

Fri Aug  3 17:46:43 PDT 2007  Duncan Coutts <duncan at haskell.org>
  * Try and simplify cleaning by always removing dist
  so we don't have to individually track all the files we create
  we still have to delete a few files outside of the build dir sadly
  the configuration is still preserved if you specify --save-configure

    M ./Distribution/Simple.hs -26 +22
    M ./Distribution/Simple/Register.hs -5 +10