cubicweb #1272103 resurrect pywebkit test case from adim's prototype [open]

In some cases, we want to validate javascript logic. pywebkit lets us write/test javascript code more easily that windmill. Wrap it by using httptest module to have a tiny cw instance to test.

And provide documentation ! :-)

priorityminor
typeenhancement
done in<not specified>
load0.500
load left0.500
closed by<not specified>