ERP5Workflow: Move StateChangeInfo from DCWorkflow.Expression to ERP5Workflow.

This reduces dependency on DCWorkflow and cleanup StateChangeInfo monkey patch.
6 jobs for master
Status Job ID Name Coverage
  External
passed ERP5.CodingStyleTest-Master

00:55:57

passed ERP5.PerformanceTest-Master

00:26:50

running ERP5.UnitTest-Master

14587:29:39

failed ERP5.UnitTest-Zope2

03:47:57

passed SlapOS.Eggs.UnitTest-Master.Python2

00:16:50

passed Wendelin.UnitTest-Master

00:35:57