Added last additions from jam (read more)

I should also mention that the client is throwing up a warning that
HandleCharacterUpdate() is passing to HandleCharacterNew().

client/scenes/main_menu.cpp

@@ -101,6 +101,7 @@ void MainMenu::MouseButtonDown(SDL_MouseButtonEvent const& button) {
 }
 
 void MainMenu::MouseButtonUp(SDL_MouseButtonEvent const& button) {
+	//TODO: Buttons should only register as "selected" when the left button is used
 	if (startButton.MouseButtonUp(button) == Button::State::HOVER) {
 		SetNextScene(SceneList::LOBBYMENU);
 	}