[Added] Services for assets and audio, main screen, simplified drawing, [Updated] Dockerfile, so the libraries get their own folder

include/Service.h

@@ -0,0 +1,23 @@
+#ifndef SERVICE_H
+#define SERVICE_H
+
+template <typename T>
+class Service
+{
+private:
+protected:
+    static T* instance;
+    Service() {}
+
+public:
+    Service(const Service &) = delete;
+    Service &operator=(const Service &) = delete;
+
+    static T& getInstance()
+    {
+        static T instance;
+        return instance;
+    }
+};
+
+#endif