code: function(){
              if(errors.length) return cb(errors);
              var transform = opts.transform || function(_result, _cb){
                _cb(null, _result);
              };
              transform(result, function(err, _result){
                if(err){
                  errors.push(formatError(err, key));
                  cb(errors);
                }else{
                  cb(null, _result);
                }
              });
            }
docs: setup function to call once all keys have been recursed