Fixed XML examples

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all
| Fixed tickets | -

Was on my todo list for quite a long time. xabbuh pushed me to do it after his PR :)

The big deal comes in the cookbook, where a lot of namespaces and xml schema paths are wrong. But I've seen enough XML for today... :dizzy: :dizzy_face: