Gantt ASP.NET demo issues

[bmblb]

Reported here: https://www.bryntum.com/forum/viewtopic.php?f=52&t=15217&p=76526

1. project includes missing files (advances.css etc)
2. js app is not built on start
3. npm packages missing because of linked package, need to add this to webpack:

module.exports = [
    {
        entry : {
            cruddemo : path.join(__dirname, 'app.js')
        },
        resolve: {
            symlinks: false
        },

Check other (not core) demos too

[isglass]

Demos updated recently for another ticket