patch applied (cabal-install): Fix reporting of installed program versions in cabal list

[Duncan Coutts]

Fri Dec 18 15:25:01 PST 2009  Duncan Coutts <duncan at haskell.org>
  * Fix reporting of installed program versions in cabal list
  We do not know if programs are installed or not so report
  unknown rather than saying it is not installed.

    M ./Distribution/Client/List.hs -1 +2

View patch online:
http://darcs.haskell.org/cabal-install/_darcs/patches/20091218232501-adfee-1eae36729c805b3792cd7d5b72abb0df56c3489e.gz