DOM based content caching added.

Normally navigation system keeps only two active pages and navbars in DOM tree. I believe this behavior was intentionally designed for performance issues. But if you are creating dynamic contents or pages and push them into navigation stack by <code>view.loadContent</code> you can't keep the older and older views in DOM tree. 

For instance; you have a registration form by 5 different steps (different html contents), you will obtain and submit all form data at the end of wizard. Currently, you can't because once you passed the page, all entered values are gone! 

That's why we need to keep pages and all related DOM elements in document tree while you were navigating deep pages.

You can simply enable caching by passing <code>{ domCache:true }</code>  to viewParams parameter of <code>app.addView</code>.