Closes#764
- All notification that were previously sent from CompactBlockProcessor are now gone.
- `CompactBlockProcessor` now provides `eventStream` to communicate with `SDKSynchronizer`.
- Added `synchronizerStoredUTXOs` notification.
- Tests are updated to not use notifications anymore. Some tests there
weren't working before are now fixed.
- Added `CompactBlockProcessorEventHandler` utility class. Previously
expectations were subscribing to notifications. This class replaces
this functionality. It subscribes to events from
`CompactBlockProcessor` and fullfill expectations.