Fix problem with jbpm parser and qnames for ItemDefinition.structureRef.
Add jBPM preference page with checkbox to disable simulation parameter
generation.
Add Relationship.type attribute required by jBPM parser.
Pull in the signed plugins for bpmn2 metamodel.
More changes to allow jbpm resources to override QName output for
specific element references.
Changed associated site URL for bpmn2 metamodel project to latest (S20130423)
Adjust BPMNEdge coordinates if the start or end waypoint lies inside
(usually at the center) of a shape.
Added drools.xsd and bpsim.xsd URIs to xsi:schemaLocation