Use workqueue

[tamalsaha]

Example: https://github.com/kubernetes/client-go/blob/master/examples/workqueue/main.go

Using workqueue solves a number of subtle bugs in writing controllers. Few important ones are:

• Ensure that one the final state of an object is handled and automatically collapses them into the final state.
• Ensures only one go routine handles an object of a kind at a time.