Add Dockerfile with Node.js and Yarn

[janpelikan]

Hi, thanks for creating azure-vm-pricing it's a really useful tool.

I'd like to kindly ask if it would be possible to add a Dockerfile to the repository, which would collect all the necessary prerequisites and dependencies (especially Node and Yarn) so that azure-vm-pricing could be used in the container.

It's not always possible/wanted to install Node.js on a workstation, but Docker would be a solution.

Thank you very much and have a nice day.