swallows logstash redis connection errors and retries every 5 seconds

for https://github.com/nlf/bucker/issues/22

Of course, the fact that this is failing should be logged somewhere, but error logging inside of a logging library is somewhat problematic. It might be possible to log to self (thought that's not `this` here), and if the user has file logging or something else, then the error will get logged there.