Surround noop packet polling with try-catch. Since node.js version 0.8.20 (http: Raise hangup error on destroyed socket write (isaacs)) a hangup
error is raised when trying to write on destroyed sockets.

fixes #1160
Merge pull request #1163 from ereslibre/0.9

Surround noop packet polling with try-catch. Since node.js version 0.8.2...