Add !queue command to show next items in the queue

configuration.ini

@@ -26,6 +26,7 @@ volume = v
 kill = kill
 stop_and_getout = oust
 joinme = joinme
+queue = queue
 
 
 [strings]
@@ -38,11 +39,15 @@ bad_file = Bad file asked
 no_file = Not file here
 bad_url = Bad URL asked
 multiple_matches = Track not found! Possible candidates:
+queue_contents = The next items in the queue are:
+queue_empty = The queue is empty!
 
 help = Command available:
        <br />!play_file <path>
        <br />!play_url <url> - youtube or soundcloud
        <br />!play_radio <url> - url of a stream
+       <br />!list - display list of available tracks
+       <br />!queue - display items in queue
        <br />!next - jump to the next music of the playlist
        <br />!stop - stop and clear the playlist
        <br />!oust - stop + Go to default channel