added a start screen and scene manager

Assets/Scripts/SceneController.cs

@@ -0,0 +1,30 @@
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+using UnityEngine.SceneManagement;
+
+public class SceneController : MonoBehaviour
+{
+    private int currentSceneIndex = 0;
+
+    // this object will always exist!
+    void Awake() {
+        DontDestroyOnLoad(this.gameObject);
+    }
+    
+    // public void NextScene() {
+    //     currentSceneIndex += 1;
+        
+    //     print("attempting to load scene " + currentSceneIndex);
+    //     if (currentSceneIndex < SceneManager.sceneCount) {
+    //         SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex + 1);
+    //     } else {
+    //         print("no more scenes!");
+    //     }
+    // }
+
+    public void NextScene() {
+        SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex + 1);
+    }
+
+}