https://forum.flowable.org/t/question-about-skip-expression-of-sequence-flow-outgoing-from-exclusivegateway/946express
https://forum.flowable.org/t/difference-between-outgoing-sequence-flows-from-usertask-and-exclusivegateway/943spa
http://blog.goodelearning.com/bpmn/bpmn-2-0-terms-explained-process-flows/blog
https://forum.flowable.org/t/how-can-i-get-the-highlightedflowids-parameter/988ip
持續更新。。。get