Workflow escalation

Goal: Make it possible to bind automation chains to nodes of the graph that are executed only if the node is "suspended" and the execution condition is verified. The execution condition can be time based. This new feature will allow to translate requirements such as "Send an email one day before the due date of a task", "automatically resume the workflow is the workflow has been started more than 10 days ago". These escalation rules are marked to be executed once or can be evaluated and executed multiple times.