patch applied (cabal): Make --user --global change the default prefix

[Duncan Coutts]

Thu Jan 10 11:38:30 PST 2008  Duncan Coutts <duncan at haskell.org>
  * Make --user --global change the default prefix
  Previously --user and --global didn't mean what it looks like they mean,
  instead of doing a per-user or a global installation they just meant to
  register in the per-user or global package databases (and to allow
  dependencies to be satisfied from the per-user or global db)
  With this patch --user / --global means to do a per-user or global install
  so in addition to the package db differences it also sets the default 
  installation prefix. This prefix can of course still be overridden using the
  --prefix= flag. The global prefix is as before, the default per-user prefix
  is $HOME/.cabal on Unix and on Windows it's something like:
  C:/Documents And Settings/$user/Application Data/cabal
  (using getAppUserDataDirectory "cabal"). This is the per-user prefix that
  cabal-install currently uses. We can change it if people think it's not good.

    M ./Distribution/Simple/Configure.hs -2 +6
    M ./Distribution/Simple/InstallDirs.hs -3 +7
    M ./Distribution/Simple/Setup.hs -9 +11