* chore(e2e): register `layout` files in bundle-config
* refactor(e2e): rename modal-layout to modal-layout-root
Similar to `modal-tab-root`:
https://github.com/NativeScript/NativeScript/tree/4.0.0/e2e/modal-navigation/app/modal-tab
This avoid the need to explicitly register it to webpack modules.
* refactor(e2e): rename mocha describes to contain a dash
* refactor: remove bundle-config
It is no more as `nativescript-dev-webpack@0.12.0` registers default application modules.
* test(e2e): update modal navigation app
Add layout as root.
Add show modal layout.
* chore(frame): move frame stack modifiers in a separate frame-stack module
* feat(frame): handle back navigation when using common layout as root element