Supported go-nsq version 1.0.0 alpha

Hi,

I modified your code to worked with the latest go-nsq version.

Most of my changes are related to go-nsq that:
[Changed method name]
- NewReader -> NewConsumer
- AddAsyncHandler -> SetHandler
- ConnectToLookupd -> ConnectToNSQLookupd
- ConnectToNSQ -> ConnectToNSQD
- Reader -> Consumer
- WriterTransaction -> ProducerTransaction
- Writer -> Producer

[Added more method parameter]
- NewConsumer added config parameter

[Deleted method/property]
- SetMaxInFlight
- MaxInFlight
- FinishedMessage

[Changed return type]
- Publish
- PublishJson
- MultiPublish
- MultiPublishAsync

I also placed "error" return type on methods that doesn't return anything for testability purposes.
And also adjusted methods description (based on golint suggestion) and included my unit tests which require a running nsqd and nsqlookupd.

Kindly review them. Thanks