Stringify packet in log message
Stringify packet in log message

This makes the packet show up as a string instead of a byte array.
Particularly important if the error will be marshaled to JSON, because
byte arrays get marshaled to base64, which is basically useless for
humans.

gphat/veneur,gphat/veneur,gphat/veneur,stripe/veneur,stripe/veneur,evanj/veneur,evanj/veneur,evanj/veneur