#41 Add support for someonly

[Sebastian Hellmann]

the refinement operator should be able to produce someonly, explicitly.
The main reason is that it is easier to convert into SPARQL.
The basic use case is, that one might turn off useAllValuesRestriction, but would allow useSomeonlyRestriction, as they would work out fine when classifying and retrieving with the OWA.
Alternatively there could be an additional refinement operator on sparql.

[Lorenz Bühmann]

Added option ForAllSemantics in class FastInstancechecker.