Fix quoting of properties

- Make AST_ConciseMethod child of AST_ObjectProperty.
- Fix some typos.

lib/transform.js

@@ -224,6 +224,9 @@ TreeTransformer.prototype = new TreeWalker;
     });
 
     _(AST_ObjectProperty, function(self, tw){
+        if (self.key instanceof AST_Node) {
+            self.key = self.key.transform(tw);
+        }
         self.value = self.value.transform(tw);
     });