NSQ-Operator v0.4.0 release

[Andy Xie]

Hi, all

After being developed for about one month off and on, Nsq-Operator has reached its v0.4.0 release. Some key features in this release is:

• CRUD nsqd/nsqlookupd/nsqadmin resources/instances
• HA. Run multiple Nsq-Operator instances by utilizing Kubernetes leaderelection package

For full features until v0.4.0, please take a look at: https://github.com/andyxning/nsq-operator#feature

With this release, end users can play with Nsq-Operator against a Kubernetes cluster in creating a nsq cluster, deleting a cluster and so on. 

Feedbacks are welcomed. :)