/*
* Get the duration of a song, in milliseconds
*
* This method raises an Xmms::Error exception if XMMS is not running,
* or an ArgumentError exception if the number of arguments isn't 0 or
* 1.
*
* Examples:
* # get the duration of the current song
* time = remote.playlist_time
*
* # get the duration of song 23 in the playlist
* time = remote.playlist_time 23
*
*/
static VALUE xr_pl_time(int argc, VALUE *argv, VALUE self) {