Find a view for a model `cell`. `cell` can also be a string representing a model `id`.
function(cell) {

        var id = _.isString(cell) ? cell : cell.id;
        
        var $view = this.$('[model-id="' + id + '"]');
        if ($view.length) {

            return $view.data('view');
        }
        return undefined;
    }