Improve stopping and wiping behavior
* Progress indicator for stopping * Progress indicator for wiping * More logging during startup and stopping for debugging * Put post wiping fragment into separate process * Improve exiting behavior on stop/wipe * Make wiping fragment display transition to stopping once wiping is done (by changing the status text view) * Make stopping and wiping take at least 1 second so that the user can perceive what's going on if these finish very quickly on fast devices * When detecting on startup, that the app is already stopping or wiping, display the stoppin/wiping fragment instead of failing silently * Exit application when reaching STOPPED state, independent of lifecycle