Update pipe.rb output - Fix LOGSTASH-1860

This adds EBADF to the rescue block as that is what is being thrown when the pipe command gets shutdown (usually due to an error.) Verified that it will restart the pipe and requeue the event that noticed that the pipe had failed and that logstash does not crash due to the pipe command failing.
Merge pull request #1034 from ronnocol/patch-1

Update pipe.rb output - Fix LOGSTASH-1860