Added fixing the xml config for most configuration options

This allows things to be specified in xml as:
```
<rabbitmq:consumer>...</rabbitmq:consumer>
<rabbitmq:consumer>...</rabbitmq:consumer>
```
instead of:
```
<rabbitmq:consumers>...</rabbitmq:consumers>
<rabbitmq:consumers>...</rabbitmq:consumers>
```

It appears the the queues option in multiple_consumers might have the same issue but I am unsure how to fix it because fixXmlConfig() doesn't appear to affect it when I tried adding it.

Fixes #197.