* src/playlist/playlist.c:

* src/playlist/playlist.c:
  - added playlist_Move to move an item in our playlist before the position
    of a previous item (or end) of our playlist. Keeps index at it's current
    item.
* modules/gui/macosx/playlist.?:
  - Now a reorderable playlist. Thanks to Andrew Stone for example code.
    This fixes #349 (Finally ;)
  - True alternating colors in the playlistview. Thanks to Apple Computer
    for the example code.