Add Imgui, Add TextureManager

From 1.1k texture loads to 5

Game/TextureManager.h

@@ -1,7 +1,20 @@
 #pragma once
+#include <map>
+
+#include "Texture.h"
 
 class TextureManager
 {
 public:
+	TextureManager() = default;
+
+	static TextureManager* GetInstance();
+
+	Texture* GetTexture(const std::string& name);
+	
+	static TextureManager* m_pInstance;
+private:
+	std::map<std::string, Texture*> m_Textures{};
 	
 };
+