Examples structure is not flexible anough to incorporate new examples

The new nix examples showed that thestructure of the examples folder is not flexible enough. Putting other examples next to it might work for one example but it starts to hold the documentation for !14 (closed) back. This is bad, I would like to change that. Maybe it would be enough to fix this on the idf-40 branch, as i believe that not much development will happen on master, until !13 (closed) is merged.

Maybe a structure of examples/<examplename> would be more flexible. We should make each example independent of the other ones, so the features we showcase in there are more cleanly visible. This would be analogue to the structure of esp-idf/examples, but i would rather not move the examples in the qthing folder as it hides them more from people exploring the repo.