Rework queue example

[jettify]

For better demo queue (producer/consumer) demo, we need to rework it. Following features should be added:

• Use real queue, like rabbigmq
• Use docker to automate start queue servcie
• Service could do simple page scraping, say user submit URL using frontend service as result workers pick it, and fetch page.

[codefromthecrypt]

cool. please ping me when readying this, so we can test that propagation is compatible with other languages.