added gamescreen UI and simple start menu

Assets/Darkmatter/Code/Presentation/UI/GameScreenController.cs

@@ -0,0 +1,40 @@
+using Darkmatter.Core;
+using UnityEngine;
+
+namespace Darkmatter.Presentation
+{
+    public class GameScreenController : IGameScreenController
+    {
+        GameScreenView gameScreenView;
+
+        public GameScreenController(GameScreenView gameScreenView)
+        {
+            this.gameScreenView = gameScreenView;
+        }
+        public void UpdateFireableBulletCount(int bulletCount)
+        {
+            gameScreenView.UpdateBulletText(bulletCount);
+        }
+
+        public void UpdateRemainingZombiesCount(int zombiesCount)
+        {
+            gameScreenView.UpdateRemainingZombiesCountText(zombiesCount);
+        }
+
+        public void UpdateTotalZombiesCount(int totalZombiesCount)
+        {
+            gameScreenView.UpdateTotalZombiesCount(totalZombiesCount);
+        }
+
+        public void ShowGameOverText()
+        {
+            gameScreenView.ShowGameOver();
+            
+        }
+
+        public void ShowPlayerHealth(int health)
+        {
+           gameScreenView.ShowPlayerHealth(health);
+        }
+    }
+}