restored interface and instance - at least for a while

src/GF/Devel/Grammar/GFtoSource.hs

@@ -38,6 +38,8 @@ trModule (i,mo) = P.MModule compl typ body where
       MTGrammar -> P.MGrammar i'
       MTAbstract -> P.MAbstract i'
       MTConcrete a -> P.MConcrete i' (tri a)
+      MTInterface -> P.MInterface i'
+      MTInstance a -> P.MInstance i' (tri a)
     body = P.MBody 
              (trExtends (mextends mo)) 
              (mkOpens (map trOpen (mopens mo)))

src/GF/Devel/Grammar/Modules.hs

@@ -54,6 +54,8 @@ type JEntry = Either Judgement Indirection
 data ModuleType =
     MTAbstract
   | MTConcrete Ident
+  | MTInterface
+  | MTInstance Ident
   | MTGrammar 
   deriving Eq
 

src/GF/Devel/Grammar/SourceToGF.hs

@@ -85,10 +85,10 @@ transModDef x = case x of
         id'   <- transIdent id
         open' <- transIdent open
         return (transCncDef, MTConcrete open', id')
-      MInterface id -> mkModRes id MTAbstract body
+      MInterface id -> mkModRes id MTInterface body
       MInstance id open -> do
         open' <- transIdent open
-        mkModRes id (MTConcrete open') body
+        mkModRes id (MTInstance open') body
 
     mkBody (trDef, mtyp', id') body
   where