feat: add on-cordova helper

[betocantu93]

Adds {{on-cordova}} helper for easier eventing on templates, this helper also implements the bubbles=false that you would expect from normal dom events so effectively mimicking stopPropatation() because this helper works as a stack, it adds a handler when executed and stops bubbling if any invocation passed bubbles false.

A demo is included in the dummy app, just open the console to see the order of which the event is executed. the practical use case is opening modals on top of each other and wanting to close them in order, avoiding a supposed /routes/application.js history.back() default handler

By the way a capacitor version is here, based on this addon: ember-capacitor-events