#27 Missing entails() method for DLReasoner.

[baz bishop]

There is no entails( <ground expression> ) method for DLReasoner.

There was one, but it was actually concept satisfiability and has been renamed accordingly.

The new entails() method will likely have to create a new private ontology with just the given ground expressiona and use one of the underlying reasoners' (pellet or kaon2) entailsOntology methods.