Hero Build/Upgrade Animation

This doesn't really effect how heros work but it will be a nice visual addition. My idea is to not use dark elixir to build the alter, instead it costs gold. Then you need to have one respective troop, barbarian for barbarian king, archer for archer queen, trained up and there will be a upgrade button which would cost dark elixir to use, which will turn the troop into a hero or upgrade the hero to the next level. When upgrading there should be a animation of it drinking dark elixir.