[FEATURE] new functionality in the nav bar

__Tasks:__
- [x] changed navigation template
- [x] added javascript to load new overlay when clicking on upload button
- [x] updated the documentation
- [ ] got feedback

__Informations:__

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| Tests pass?   | none
| Fixed tickets | none
| Doc           | none