Improve our /docs with configuration samples

[troessner]

#1058 made me realize that our docs are still far from perfect. Something like this might seem good enough for power users but for it is repellent for new users.

I think that most if not all our smell detectors should have some configuration samples at the end.
It is not much effort for us and it will make things so much easier for users.
And yes, that would not be DRY at all. Sometimes DRY is bad and I feel that this is exactly one of those places.

[troessner]

Dup to #1139 - closing this one.