Ref #8

Creates a producer process and one consumer process per partition. Uses
`multiprocessing.Queue` for communication between the parent process and
the producer/consumers.

```python
kafka = KafkaClient("localhost", 9092)
q = KafkaQueue(kafka, client="test-queue", partitions=[0,1])
q.put("test")
q.get()
q.close()
kafka.close()
```

Ref #8

Fixes #2

Can now:

```python
import kafka
kafka.KafkaClient("localhost", 9092)
```

or

```python
from kafka.client import KafkaClient
KafkaClient("localhost", 9092)
```

or

```python
import kafka.client
kafka.client.KafkaClient("localhost", 9092)
```

Snappy will go there when I get around to it