Add new operations for handling workflows

Add the following operations

• Cancel Workflow
  parameters :
  • workflow instance id

• Start Workflow (already exists, but should be improved
  parmeters:
  • workflow model id (Id of the model to use for instantiating the workflow)
  • workflow variables: Properties (like in Update Properties operation) (so as to set some workflow variables right at the start up)
  • workflow instance id variable name (variable name in the context where to store the instance ID that is just created).

• Set Workflow variable
  • workflow instance id ( if null, than applies to current workflow)
  • name/value

• Resume Node (close all the tasks of the node id referenced)
  • Worflow Instance id
  • Workflow NodeModelId ( if null, than applies to the current node of the current workflow in the context)

• GetOpenTasks
  • Returns all open tasks on the input document. If the operation is invoked
    with parameters, all tasks instances for the given 'processId' originating
    from the given 'nodeId' are returned. The 'processId' is the id of the
    document representing the workflow instance. The parameter 'username' is used
    to fetch only tasks assigned to the given user. Tasks are queried using an
    unrestricted session.

• CompleteTaskOperation
  • Completes the input task. If this is the last task the workflow will continue. Returns back the task document. "Status" is the id of the button the user would have clicked to submit the task form (if the outgoing transitions of the workflow node that created the task have conditions depending on it).