Reply details and has_reply filter on participations

• Participations now include a reply object with the reply sent to the end customer: its date, its content, its sender and its type (text for a written reply, call for a phone call). It is null when there is no reply yet.
• The Responses API accepts a new has_reply filter: GET /responses?has_reply=false lists the participations that have not been replied to yet.

See Participation retrieval for details.