patch applied (packages/base): Fix negative index handling in splitAt, replicate and unfoldrN. Move mapF, filterF -> map' , filter' while we' re here

[Don Stewart]

Tue May 16 19:01:50 PDT 2006  Don Stewart <dons at cse.unsw.edu.au>
  * Fix negative index handling in splitAt, replicate and unfoldrN. Move mapF, filterF -> map', filter' while we're here

    M ./Data/ByteString.hs -13 +17
    M ./Data/ByteString/Char8.hs -6 +6