[BUGFIX] Internal link node load error and to array bug

__Tasks:__

- [ ] gather feedback for my changes
- [ ] submit changes to the documentation

__Informations:__

| Q             | A
| ------------- | ---
| Tests pass?   | yes
| Fixed tickets | https://github.com/sulu-cmf/SuluWebsiteBundle/issues/45
| BC Breaks     | none
| Doc           | none