WIP: Better windows support + adjustments

[WoLfulus]

NOTE: This is a work-in-progress

So i'm making some changes to the base project for a better Windows support and there are several things I'll be doing here:

• Add a configurable port through env variables
• Add a make.bat to simulate make commands on windows
• Enable chokidar's polling in make.bat to properly rebuild files when running Docker for Windows
• Normalize access to both backend and frontend through a load balancer to avoid exposing multiple ports and GRAPHQL_HOST-like stuff
• Enable proper logging and shutdown/failure behaviours by making nginx and php-fpm both s6 overlay services
• Cleanup Dockerfile

Also it should solve #7 and #4

BTW, I'd love to hear some feedbacks on this so I can know if this makes sense or not.

Thanks :)