use higher-level Data.Binary.Put not Builder
DRY
tear down socket once we've used it
inline sendMessage, so we can receive on same socket later
send a valid ntp control message

this message will actually get a response from an ntp server (you can
see it with tcpdump).
receive response and dump to stdout
Merge pull request #2 from philandstuff/master

send an ntp control message and receive a response