If this is a bug report, please fill out the following:

* Version of Ruby:
* Version of Kafka:
* Version of ruby-kafka:

Please verify that the problem you're seeing hasn't been fixed by the current `master` of ruby-kafka.

###### Steps to reproduce

```ruby
kafka = Kafka.new(...)

# Please write an example that reproduces the problem you're describing.
```

###### Expected outcome

What you thought would happen when running the example.

###### Actual outcome

What actually happened.
