Enemy spawning code now reference COLS and ROWS constants; removed

extraneous enemy_count removal.

enemy.gd

@@ -43,9 +43,10 @@ func explode():
     if exploding: return
     exploding = true
     print_debug("Enemy explode!")
+    EventBus.enemy_hit.emit(5)
     speed = 0
     $AnimationPlayer.play("explode")
     set_deferred("monitoring", false)
-    EventBus.enemy_died.emit(5)
     await $AnimationPlayer.animation_finished
     queue_free()
+    EventBus.enemy_died.emit()