cubicweb-container #2800641 complete the doc [resolved]

Give a very simple introductive example.
With credible use cases.

prioritynormal
typeenhancement
done in1.0.2
load0.500
load left0.000
closed by#fe53b8db0cc5 add a small example in the documentation (closes #2800641)
patch(wip) add a small example in the documentation (closes #2800641) [applied]