Add an option to only activate the client on click

I want an option to only initialize the world once the canvas is clicked. It should have a secondary option for the message that displays on the canvas until they click it (e.g. "Click here to join my world") that can be overridden by the implementer.

This will depend on some logic rewrites to allow late loading the world and associated components (instead of in the constructor) as well as possibly some new bindable events (e.g. world.create).

First usage of this will be on the examples/tutorials page of the gh-pages branch, where each example would have a frojs instance that shows off the unique configuration.