Pull up singleton behaviour.

Assets/Cryville/Crtr/UI/Master.cs

@@ -1,24 +1,13 @@
-using System;
+using Cryville.Common.Unity;
 using UnityEngine;
 
 namespace Cryville.Crtr.UI {
-	internal class Master : MonoBehaviour {
-		static Master s_instance;
-		public static Master Instance { get { return s_instance; } }
-
+	internal class Master : SingletonBehaviour<Master> {
 #pragma warning disable IDE0044
 		[SerializeField]
 		private GameObject m_menu;
 #pragma warning restore IDE0044
 
-		void Awake() {
-			if (s_instance != null) {
-				Destroy(gameObject);
-				throw new InvalidOperationException("Attempted to initialize a singleton twice.");
-			}
-			s_instance = this;
-		}
-
 		internal void ShowMenu() { m_menu.SetActive(true); }
 		internal void HideMenu() { m_menu.SetActive(false); }