Improved Delay component

At its current state, the "Delay" component do not do anything when the delay ends. This modification fixes that, allowing you to pass a "callbackOff" method that will be called after all iterations of delay are executed.

Also, now it's possible to cancel a delay with the method .cancelDelay, passing as argument a method reference, the same method reference passed to .delay.

Finally, fixed a minor inconsistency in the the comments.