[devtools] bases for instrumenting / debugging standard propagation hooks
* a class that helps writing command to check propagation, detecting standard
errors and picture the propagation as a graph
* a class to instrument sets used to configure standard propagation hooks
closes #3171980
Essayer le champ de recherche. Essayer des recherches comme "fiche
unmotachercher", ou encore "fiche wikiid index" ou "345".