move NumeralX.inc to ParamX since it is used in many places

src/russian/NumeralRus.gf

@@ -455,12 +455,6 @@ lincat
       _  => BIND
       } ;
 
-    inc : DTail -> DTail = \t -> case t of {
-      T1 => T2 ;
-      T2 => T3 ;
-      T3 => T1
-      } ;
-
   oper
 
   mk3Dig : Str -> Str -> NumSize -> TDigit = \c,o,size -> mk4Dig c o Pl size ;
@@ -476,4 +470,4 @@ lincat
     s : Str ;
     size : NumSize
   } ;
-}
+}