Implement IConfirmNavigation & IConfirmNavigationAsync

# Description

Prism Navigation requires the ability to prevent navigation or to stop additional Navigation.

## Scenario 1 - Initial Navigation

You have an empty Navigation Stack... there is nothing to confirm

## Scenario 2 - Pushing a single Page

You have a Navigation Stack `ViewA/ViewB`, you would like to navigate to `ViewC`

This should call ViewB to validate that we can navigate from ViewB to ViewC

## Scenario 3 - Pushing multiple Pages

You have a Navigation Stack `ViewA`, you would like to navigate to `ViewB/ViewC`

- This should call ViewA to verify we can navigate to ViewB.
- We should Create ViewB, Apply Parameters (Initialize it), push it onto the Navigation Stack
- We should then call ViewB to verify that we can navigate to ViewC

If ViewB returns false then we should be left with a Navigation Stack that looks like `ViewA/ViewB`, otherwise we continue navigating.

## Scenario 4 - Resetting the navigation stack

You have a Navigation Stack like `ViewA/ViewB`, you want to navigate to `/ViewC`

This should call ViewB to validate that we can navigate from ViewB to ViewC