[WIP] column navigation

column navigation for nodes (pages-/content-elements)

- [ ] finish the code
- [ ] gather feedback for my changes
- [ ] submit changes to the documentation


| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| Tests pass?   | [yes|no|none]
| Fixed tickets | none
| Doc           | [url to doc|none]