When running on lots of hosts with a large login banner on a slow network, it was still possible that the first recv() didn't to pull in the sudo password prompt, and sudo would fail intermittently.  This patch tells sudo to use a specific, randomly-generated prompt and then reads until it finds that prompt (or times out).  Only then is the password sent.  It also catches `socket.timeout` and thunks it to a more useful `AnsbileError` with the output of sudo so if something goes wrong you can see what's up.