Merge pull request elastic#1665 from mfournier/LOGSTASH-1886-2nd_try

LOGSTASH-1886: intercept exception raised by march_hare

Author: jordansissel

lib/logstash/outputs/rabbitmq/march_hare.rb

@@ -44,7 +44,7 @@ def publish_serialized(message)
         else
           @logger.warn("Tried to send a message, but not connected to RabbitMQ.")
         end
-      rescue MarchHare::Exception, com.rabbitmq.client.AlreadyClosedException => e
+      rescue MarchHare::Exception, IOError, com.rabbitmq.client.AlreadyClosedException => e
         @connected.set(false)
         n = 10