fix NoMethodError: undefined method `body' for #<Airplay::Connection::Response:0x007f800520eb58>

Player#scrub raised NoMethodError: undefined method `body' for #<Airplay::Connection::Response:0x007f800520eb58>
Merge pull request #65 from ronald/patch-1

fix NoMethodError: undefined method `body' for #<Airplay::Connection::Re...