function serve(args) {
    var options = {
        script: paths.server + 'app.js',
        delayTime: 1,
        env: {
            'NODE_ENV': args.mode,
            'PORT': port
        },
        watch: [paths.server]
    };

    var exec;
    if (args.debug) {
        log('Running node-inspector. Browse to http://localhost:8080/debug?port=5858');
        exec = require('child_process').exec;
        exec('node-inspector');
        options.nodeArgs = [args.debug + '=5858'];
    }

    return plug.nodemon(options)
        .on('start', function() {
            startBrowserSync();
        })
        //.on('change', tasks)
        .on('restart', function() {
            log('restarted!');
            setTimeout(function () {
                browserSync.reload({ stream: false });
            }, 1000);
        });
}
Start the node server using nodemon.
Optionally start the node debugging.
@param  {Object} args - debugging arguments
@return {Stream}