new call state: participant
Issue generated from Tuleap's migration script. Originally submitted by: Nicolas Jager (nicolasjager-sfl)
the summoner of a conference knows that the call is a conference trough :
but for the participants, the conference is like usual call :
wich leads to have two previews on participants screens. I propose to add a new state and let the conference summoner to tell to the participants that they are currently involved in a conference with it.
In that case we could shutdown the preview.