Interop sample updates

[stagg]

Description

Collection of fixes and changes in the interop sample to get it back up to speed and working.

Changes

Update readme to include the interop project

• Didn't have the interop sample listed in the samples readme

Fix bug where the screen wouldn't update on selection

• Changing the presenter or ui sources was not updating as only the initial screen was captured in the movableContentOf

Break the dependency on the counter sample

• Wasn't really a need to be dependent on the other sample, will make it easier to update the counter sample too

Fix CounterView not calling back on right event sink

• When the UI was the view and the presenter was switched the event sink wasn't getting updated to the latest