use correct types for mapping

src/main/jastadd/Ros2Rag.relast

@@ -10,7 +10,4 @@ rel TokenSyncDefinition.token -> TokenComponent;
 ReadFromMqttDefinition : TokenSyncDefinition;
 WriteToMqttDefinition  : TokenSyncDefinition;
 
-MappingDefinition ::= <ID> <Content> ;
-
-rel MappingDefinition.from -> TypeDecl;
-rel MappingDefinition.to -> TypeDecl;
+MappingDefinition ::= <ID> From:JavaTypeUse To:JavaTypeUse <Content> ;