Support business rules invocation

[adamfowleruk]

As per BPMN2 spec

Implement via semantic inferencing?

From BPMN2 spec PDF page 163:- "A Business Rule Task provides a mechanism for the Process to provide input to a Business Rules Engine and to get the output of calculations that the Business Rules Engine might provide. The InputOutputSpecification of the Task (see page 211) will allow the Process to send data to and receive data from the Business Rules Engine."