Fix: Hiding GoToDonkey-Icon, when accessing donkey from a second computer
If donkey is not bought on an account, the donkey info panel is not shown
Ensured that dummy entry in donkey info panel is only set, when "you already have visited donkey" message appears
Substituted German error message with response error code
Merge pull request #31 from MoeLa/MultiUserDonkey

Handling donkey behavior, when using more than one computers to play