grunt task partial for starting a watch task and server in a build folder

serve.js

/*jshint node:true, laxbreak:true */
'use strict';

module.exports = function(grunt) {
    grunt.config.merge({
        browserSync: {
            bsFiles: {
                src: '<%= env.DIR_DEST %>/**/*'
            },
            options: {
                watchTask: true,
                server: {
                    baseDir: '<%= env.DIR_DEST %>'
                }
            }
        }
    });

    grunt.registerTask('serve', [
        'browserSync', 'watch'
    ]);
};