1) Simplify SharedPreferences management
2) Shut down signalManager/splitManager to avoid random crashes
3) Get rid of sharedPreferencesChanged from the service interface
All tests pass.
In particular:
1) Add a workaround to {start/end}Recording to update recordingTrackId to trigger a notification
2) Add a bunch of unit tests for MyTracks
3) Clear minor style issues in a few classes
Bartlomiej Niechwiej