mkm3u: Make `AudioEpisode' a subclass of `AudioDisc' like it should be.

diff --git a/mkm3u b/mkm3u
index 21c9a4b..f99d8ca 100755 (executable)
--- a/mkm3u
+++ b/mkm3u
@@ -249,9 +249,7 @@ class AudioDisc (Source):
   PREFIX = "file://"
   TITLEP = CHAPTERP = False
 
-class AudioEpisode (Source):
-  PREFIX = "file://"
-  TITLEP = CHAPTERP = False
+class AudioEpisode (AudioDisc):
   def __init__(me, fn, i, *args, **kw):
     super().__init__(fn, *args, **kw)
     me.i = i