fix: signal handling (#1375)

* fix: signal handling

* fix: flush WorldServer logger before main loop

* fix: consolidate signal code

dCommon/Game.cpp

@@ -0,0 +1,7 @@
+#include "Game.h"
+
+namespace Game {
+	void OnSignal(int signal) {
+		lastSignal = signal;
+	}
+}