* Added common functions for handling relative paths in playlist files
 * Module declaration for pls import module
modules/demux/playlist/m3u.c:
 * implemented m3u import module
modules/demux/playlist/pls.c:
 * new pls import module
modules/demux/playlist/playlist.h:
 * common prototypes
modules/demux/playlist/Modules.ac
 * activated pls module