[agent] align generated creneaux with overlapping RDVs and absences
Created by: adipasquale
https://trello.com/c/AGzPGXNf/959-agent-ajuster-les-cr%C3%A9neaux-propos%C3%A9s
Created by: adipasquale
https://trello.com/c/AGzPGXNf/959-agent-ajuster-les-cr%C3%A9neaux-propos%C3%A9s