Allow trailing comma

json11.cpp

@@ -769,6 +769,8 @@ struct JsonParser final {
                     return fail("expected ',' in object, got " + esc(ch));
 
                 ch = get_next_token();
+                if (ch == '}')
+                    break;
             }
             return data;
         }
@@ -792,6 +794,8 @@ struct JsonParser final {
                     return fail("expected ',' in list, got " + esc(ch));
 
                 ch = get_next_token();
+                if (ch == ']')
+                    break;
                 (void)ch;
             }
             return data;