Change the script to SongsAlt

Author: badlydrawnrob

Diff for: how-to-elm/04-custom-types-songs.html

@@ -12,7 +12,7 @@
 
   <script src="04-custom-types-songs.js"></script>
   <script>
-    Elm.CustomTypes.Songs.init({
+    Elm.CustomTypes.SongsAlt.init({
       node: document.getElementById('main')
     });
   </script>