fix: use ViewUtils to add Component to Page

Without this the Page and componentView doesn't get the proper relation
for then the page is destroyed.

Author: m-abs

nativescript-angular/router/page-router-outlet.ts

@@ -359,7 +359,7 @@ export class PageRouterOutlet implements OnDestroy { // tslint:disable-line:dire
         // Remove it from original native parent.
         this.viewUtil.removeChild(componentView.parent, componentView);
         // Add it to the new page
-        page.content = componentView;
+        this.viewUtil.insertChild(page, componentView);
 
         page.on(Page.navigatedFromEvent, (<any>global).Zone.current.wrap((args: NavigatedData) => {
             if (args.isBackNavigation) {