Add vscode devcontainer / github codespaces

[sduquemesa]

Context: Have you dream of having many and completely environments (down to the operative system) on your local machine or even making changes to the walrus online?

Description of the Change: This PR implements a fully furnished vscode devcontainer.

Benefits:

• Can create fully reproducible environments on different machines
• Enables (paid) github codespaces
• Allows you to run/debug the walrus on linux even when on a mac or windows machine

How-to?

• To try it out the devcontainer locally on vscode follow the instructions here,
• Use (paid, yes you pay so be careful with usage) github codespaces

Possible Drawbacks: 🤷

Related GitHub Issues: None