extended functor syntax

doc/tutorial/music/MusicEng.gf

@@ -1,7 +1,11 @@
 --# -path=.:present:api:prelude
 
-  concrete MusicEng of Music = MusicEng0 - [PropKind] ** 
-      open SyntaxEng in {
+  concrete MusicEng of Music = 
+    MusicI - [PropKind] 
+      with
+        (Syntax = SyntaxEng),
+        (MusicLex = MusicLexEng) ** 
+    open SyntaxEng in {
   lin
     PropKind k p = mkCN k (mkRS (mkRCl which_RP (mkVP p))) ;
   }

doc/tutorial/music/MusicEng0.gf

@@ -1,3 +0,0 @@
-  concrete MusicEng0 of Music = MusicI with
-    (Syntax = SyntaxEng),
-    (MusicLex = MusicLexEng) ;