Implement Paging for DAO SPI implemenation

[ridoo]

Database paging via Hibernate API. Actual mechanism (multiple mechanism possible) has to be determined.

Use a Paginated object to hold page info and add it to the actual output.

Revise Paging section in documentation. Have a look at serving partial content via Content-Range and decide to use it (or not).

[nuest]

@autermann often pointed out the lack of paging and might be able to provide some insight or ideas.

[CarstenHollmann]

To ensure no objects are returned twice the ORDER BY statemente must be added to the db queries because the dbms does not guarantee the same result order if the request is executed again.

[ridoo]

@SpeckiJ is there any update on this? :)