KataPageManager - implement better back button handling. #144
Description
Back buttons are currently have preconfigured pages to go to rather than being generic and just allowing to return the user to the previous page they were in. We should be able to call KataPageManager.ReturnToPreviousPage() from anywhere rather than having to control that flow ourselves.
The main thing we need to be aware of is not letting back buttons count as a part of page "memory" otherwise you'll end up looping to the same page by pressing back twice.
The intended flow should be something like:
User starts at Page 1 -> User clicks Page 2 -> User Clicks Page 3 -> User clicks back and returns to Page 2 -> User clicks back again and returns to Page 1.
We also need to handle supporting multiple pages at once, which could be abstracted into a PageGroup.
This whole system might be as simple as just keeping a stack of PageGroups, pushing to the stack whenever we enter a page, and popping whenever he return but I expect there to be some edge cases to handle with page groups and returning.