BPMSPL-70 - EJB interface for BPM execution server

- refactoring of services structure and api definition, separated cdi code into separate module so services themselves are framework independent

- ejb implementation and test cases for jboss arquillian mode - local ejb only

- remote ejb implementation and test cases
BPMSPL-70 - added dedicated exceptions to indicate missing deployment, process instance, task, work item, added new modules to jbpm distribution
Lazy initialization of ksession and task service when fetching runtime engine, lazy by default with option to switch to eager
JBPM-4225 - Provide data base backed storage for deployments
BPMSPL-70 - added support for paging and sorting capabilities for services