[FEATURE] Added Controller, interfaces, fixtures and entities for product attributes

Added Controller, interfaces, fixtures and entities for product attributes:

__Tasks:__

- [x] added AttributeController
- [x] added Interfaces
- [x] added attributeType entity
- [x] added attributeType fixtures
- [ ] gather feedback for my changes



__Informations:__

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| Tests pass?   | none
| Fixed tickets | none
| Doc           | none