Add a dropdown on participate menu, disallow listing participations

Now requires quering the person endpoint to know if an actor
participates in an event, organizers can make authenticated requests to
event { participants { } } to see the pending / approved participants.

Also closes #174

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

js/src/views/Event/Participants.vue

@@ -68,6 +68,7 @@ import { IPerson } from '@/types/actor';
           page: 1,
           limit: 10,
           roles: [ParticipantRole.PARTICIPANT].join(),
+          actorId: this.currentActor.id,
         };
       },
     },
@@ -79,6 +80,7 @@ import { IPerson } from '@/types/actor';
           page: 1,
           limit: 20,
           roles: [ParticipantRole.CREATOR].join(),
+          actorId: this.currentActor.id,
         };
       },
       update: data => data.event.participants.map(participation => new Participant(participation)),
@@ -91,6 +93,7 @@ import { IPerson } from '@/types/actor';
           page: 1,
           limit: 20,
           roles: [ParticipantRole.NOT_APPROVED].join(),
+          actorId: this.currentActor.id,
         };
       },
       update: data => data.event.participants.map(participation => new Participant(participation)),