$scope.$on('collaborator-removed', function (event, collaborator){
                $scope.collaborators.$promise.then(function (){
                    var index = $scope.collaborators.indexOf(collaborator);
                    $scope.collaborators.splice(index, 1);
                });
            });

            $scope.$on('collaborator-created', function (event, collaborator){
                $scope.collaborators.$promise.then(function (){
                    $scope.collaborators.push(collaborator);
                })
            });

            $scope.remove = function (collaborator){
                Collaborators.delete(collaborator);
                $scope.$parent.$broadcast('collaborator-removed', collaborator);
            };

            $scope.shared = function (collaborator){
                console.debug(collaborator);
                $scope.$parent.$broadcast('collaborator-created', collaborator);
            };