Add some getter and setter to DelegateTask.
Add getDelegationState() in DelegateTask.
Fixed url: Get diagram for a process instance
Fix for ACT-1934
Fix for ACT-1934, updated unit test to look for Task Listener Field Extension.
Update usertaskmodel.bpmn
Update UserTaskXMLConverter.java
Update UserTask.java
Update UserTaskParseHandler.java
Update UserTaskConverterTest.java
ACT-2073 Document custom identity link feature in User Guide
ACT-2062: FeatureDescriptor's setValue method will not accept a null value
ACT-2068 update for redundant namespace usage

related to ACT-2023 - missed subprocess call
ACT-1963 Data Object support for Activiti Modeler

Removed the joda dependency for XML and JSON conversion and used default
SimpleDateFormat similar to the runtime due date values.

Updated the xml conversion code and tests to use the same formats
simplified the test comparison (got rid of Calendar code).

Fixed NPE when data objects have no value - similar issue to ACT-2005
for Designer code.

Change Id: 6b6768fea020d4bf6907866652f4262f8bb0fee1
Added feature that allows a Camel header to be used for setting the
Initiator on the workflow instance.
TASK_TIMEOUT
Added a section to User Guide on how to override SessionFactory and
plugin new classes for custom identity management solution.
JSON owner and custom identity links json conversion
added support in modeler
Cleanup tests
Cleanup event tests