Feature/synthetic workflow

Synthetic workflow allows for limited execution of Workflow Processes outside the context of the AEM Workflow Engine. Synthetic WF is ideal for applying business logic encapsulated in WF Processes at scale (ex. content migration, application of new WF against existing content, etc.)

* Synthetic WF only supports OSGi WorkflowProcesses 
* Synthetic WF does not support delegating WF, routing (unsupported operations throw an UnsupportedOperationException)
* Supports complete/terminate/restart (TBD if restart is a good idea to support)

WDYT?