index.js
function done(err, result) {
                if(err) {
                    def.reject(err);
                    callback(err);
                    return;
                }

                def.resolve(result);
                callback(undefined, result);
            }
function done(err, result) {
                if(err) {
                    def.reject(err);
                    callback(err);
                    return;
                }

                def.resolve(result);
                callback(undefined, result);
            }
function done ( err , result ) { if ( err ) { def . reject ( err ) ; callback ( err ) ; return ; } def . resolve ( result ) ; callback ( undefined , result ) ; }
This method will be invoked when the seeding is completed or when something
went wrong. This method will then call the callback and rejects or resolves
the promise object. This way, users of the library can use both.

@param  {*}        err    [description]
@param  {Object}   result [description]
This method will be invoked when the seeding is completed or when something went wrong . This method will then call the callback and rejects or resolves the promise object . This way users of the library can use both .