Update of installation related files (requirements.txt and backend_server.js.example)

Created by: marcus-oscarsson

Hello everybody !

So I'm back to work with MxCuBE, I hope you guys will enjoy it as much as I do :). I just got started and while installing MxCuBE I made some smaller updates to installation related files. I think the diff basically speaks for itself nothing that really needs to be explained

Thanks, and its nice to be back ! Marcus