replace combined stateUpdated signal with individual events

src/lib/eventsystem/event/BossWaveUpdatedEvent.h

@@ -0,0 +1,17 @@
+#ifndef BOSS_WAVE_UPDATED_EVENT_H
+#define BOSS_WAVE_UPDATED_EVENT_H
+
+#include "Event.h"
+#include "Tick.h"
+
+class BossWaveUpdatedEvent : public Event
+{
+public:
+	BossWaveUpdatedEvent(int counter, Tick countdownTicks)
+	    : counter(counter), countdownTicks(countdownTicks) {}
+	const int  counter;
+	const Tick countdownTicks;
+};
+
+#endif   // BOSS_WAVE_UPDATED_EVENT_H
+