Add error handling for MQTT DNS lookup issue: "Unable to connect (Lookup error.).".

Author: airdrummingfool

support/mqtt

@@ -165,6 +165,7 @@ mqtt_error_handler () {
 		#ERRORS 
 		[[ ${received^^} =~ .*REFUSED.* ]] && return_value=1 && print_message="mqtt broker refused connection - check username, password, and host address"
 		[[ ${received^^} =~ .*NETWORK.* ]] && return_value=0 && print_message="network is down. enqueuing command to try again after a delay"
+		[[ ${received^^} =~ .*"LOOKUP ERROR".* ]] && return_value=0 && print_message="issue connecting to mqtt server (lookup error). enqueuing command to try again after a delay"
 
 		if [ -n "$last_error_message" ] && [ "$last_error_message" == "$print_message" ]; then 
 			#HERE, WE HAVE A REPEATED ERROR