Adds flattener for ComposedModel

modules/swagger-codegen/src/main/java/io/swagger/codegen/InlineModelResolver.java

@@ -179,6 +179,10 @@ public class InlineModelResolver {
                             }
                         }
                     }
+                } else if (model instanceof ComposedModel) {
+                    ComposedModel m = (ComposedModel) model;
+                    Map<String, Property> properties = m.getChild().getProperties();
+                    flattenProperties(properties, modelName);
                 }
             }
         }