Improve extensibility of drools extension in KIE Server

Currently Drools extension in KIE Server expects data in String format that then are transformed into object representation via marshallers. While this is completely ok for REST and JMS it might be a limitation when other type of transports are required - socket communication with binary data, Apache Mina, Netty, etc

Current solution should be improved to allow direct use of rule service that will be responsible for:

• finding ksession to use
• executing commands
• returning results

such service should be then wrapped with implementation that deal with given transport like REST and JMS based on string payload and marshaller. Custom implementation could then decide how to deal with different types of data handling and directly call the rule execution service to avoid sting based transformation