patch applied (cabal-install): Use relative paths when makeing tar.gz rather than changing current dir

[Duncan Coutts]

Tue Mar 18 18:39:36 PDT 2008  Duncan Coutts <duncan at haskell.org>
  * Use relative paths when makeing tar.gz rather than changing current dir
  The current directory is a global variable, we should not mutate it.
  So instead, pass a base and relative path when generating tar entries.
  Also change sanitizePath to be pure and use FilePath.Poisx.

    M ./Hackage/Tar.hs -32 +40

View patch online:

  http://darcs.haskell.org/cabal-install/_darcs/patches/20080319013936-adfee-5ec4b3fdc9737c5123863abd7f8a8eab92f354e9.gz