Replace not implemented functions with noop. Fixes #4

Removes the error which was thrown until now.
iron:router users are encouraged to implement all routes on client and server (see [README.mb](https://github.com/EventedMind/iron-router/blob/f80d2b5c9bf3b680aeb5974d430884804015cbe7/README.md#routes-on-client-and-server) and [#944](/EventedMind/iron-router/issues/944)). This resulted in errors when any of the client side routes used `.wait` or `.ready`.