Test runner: Detect extra property in 'actual' but not in 'expected'. (#407)

* Test runner: Detect extra property in 'actual' but not in 'expected'.

Also update all expected.json where this would result in errors.

* Include rmExpected.js script in case it is needed again

test/fixtures/jsx/basic/8/expected.json

@@ -141,7 +141,8 @@
                         "end": {
                           "line": 1,
                           "column": 7
-                        }
+                        },
+                        "identifierName": "x"
                       },
                       "name": "x"
                     },
@@ -271,7 +272,7 @@
           "children": []
         }
       }
-    ]
-  },
-  "comments": []
+    ],
+    "directives": []
+  }
 }