JBPM-XXXX: Compensation

- Fixed parser to throw error when sequence flow is used instead of associations
- Saving association elements differently in order to link compensations
- Added support for simple association based compensation
- Added BroadcastEventTypeFilter to deal with broadcast Compensation events
- Added direction field to Association
- Moved List<Association> from Definitions to RuleFlowProcess.metaData

rebase main
JBPM-????: Compensation testing
rebase test
rebase test
Compensation: marshalling
flow: split me into clean-up and comp
bpmn2: split me into clean-up and comp