Introduce Menu class

src/Menu.cpp

@@ -0,0 +1,23 @@
+#include "Menu.h"
+
+Menu::Menu(Framebuffer *p_framebuffer, ShaderProgram *p_shaderProgram) :
+    framebuffer(p_framebuffer), shaderProgram(p_shaderProgram)
+{
+    mainMenuScreen = new Screen(screenType::mainMenu, framebuffer, shaderProgram);
+    pauseMenuScreen = new Screen(screenType::pauseMenu, framebuffer, shaderProgram);
+    loadingScreen = new Screen(screenType::loadingScreen, framebuffer, shaderProgram);
+    optionMenuScreen = new Screen(screenType::optionMenu, framebuffer, shaderProgram);
+}
+
+Menu::~Menu()
+{
+    delete mainMenuScreen;
+    delete pauseMenuScreen;
+    delete loadingScreen;
+    delete optionMenuScreen;
+}
+
+void Menu::showLoadingScreen()
+{
+    loadingScreen->draw();
+}