Meteor.Error: Fix self.error comment

packages/meteor/errors.js

@@ -80,8 +80,7 @@ Meteor.Error = Meteor.makeErrorType(
   function (error, reason, details) {
     var self = this;
 
-    // Currently, a numeric code, likely similar to a HTTP code (eg,
-    // 404, 500). That is likely to change though.
+    // String code uniquely identifying this kind of error.
     self.error = error;
 
     // Optional: A short human-readable summary of the error. Not