Preview Handling

Preview Handling:

- [x] test coverage
- [x] finish the code
- [ ] gather feedback for my changes
- [x] submit changes to the documentation

Fixed Tickets:

- [x] Bugfixes
- [x] #23 
- [x] #57  
- [x] #48 
- [x] #41 
- [x]  #40 (small changes in husky https://github.com/massiveart/husky/pull/221 and https://github.com/sulu-cmf/SuluTagBundle/pull/24)
- [x] #39 
- [x] #30 
- [x] #37

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| Tests pass?   | none
| Fixed tickets | see above
| Doc           | none