Game start

When the game is first launched, the default menu is shown and only then can the game really start :

• display blue "player one" and yellow "Ready" on the map
• the game freeze (TBD, specific amount of frames, maybe about 2 seconds)
• load ghosts and hide blue "player one"
• another game freeze (about 2 seconds)

As per the following example : https://youtu.be/7O1OYQRqUag?t=13