Audio manager

Similar to what we did for textures and fonts, we're going to need a way to manage sf::SoundBuffer instances easily. Luckily, our ResourceManager class is there to make it extremely convenient, so let's create the AudioManager.h file and define the way sound buffers are set up:

class AudioManager : public ResourceManager<
  AudioManager, sf::SoundBuffer>
{
public:
  AudioManager() : ResourceManager("audio.cfg"){}

  sf::SoundBuffer* Load(const std::string& l_path){
    sf::SoundBuffer* sound = new sf::SoundBuffer();
    if (!sound->loadFromFile(
      Utils::GetWorkingDirectory() + l_path))
    {
      delete sound;
      sound = nullptr;
      std::cerr << "! Failed to load sound: "
        << l_path << std::endl;
    }
    return sound;
  }
};

As you can tell already, the sound interface is pretty much exactly the same as that of textures or fonts. Similar to the previous resource managers, we also provide a file...