Added docker build support

[ToberoCat]

As mentioned in #721 after the build process worked for me, I'll create a pull request, so others don't have to go through the tedious process of fixing buildroot issues with the docker ubuntu image.

Docker allows to run a linux image that, in this case, only builds the project, with the required libraries installed by default.

In this pull request I added following files:
Dockerfile - These are the instructions to create the image with all required packages
docker-compose.yml

I modified this file:
README_PINN.md - I added a section at the bottom for build instructions for PINN with an docker files using the files added in this pull request.

For anything, that might prevent this pull request from getting merged, I'd be happy to be notified about, so I can fix them

[procount]

Thanks for sorting this. I must give it a try. Is this docker image suitable for Windows, Linux x86/AMD64 or Arm?

[ToberoCat]

Yes, the docker file will create a image on any operating system, as long as it supports docker.