Portal restructuring

Changes to be compatible to the new portal structure.
Should be mergeable after https://github.com/sulu-cmf/sulu/pull/21

- [x] test coverage
- [x] finish the code
- [x] gather feedback for my changes


| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| Tests pass?   | yes
| Fixed tickets | no
| Doc           | https://github.com/sulu-cmf/docs/blob/master/detail-specification/000-foundation/DET-004-Routing.md