patch applied (packages/base): add WordPtr and IntPtr types to Foreign.Ptr, with associated conversions

[Simon Marlow]

Tue May  9 02:26:06 PDT 2006  Simon Marlow <simonmar at microsoft.com>
  * add WordPtr and IntPtr types to Foreign.Ptr, with associated conversions
  
  As suggested by John Meacham.  
  
  I had to move the Show instance for Ptr into GHC.ForeignPtr to avoid
  recursive dependencies.

    M ./Foreign/Ptr.hs -17 +47
    M ./GHC/ForeignPtr.hs -4 +22