Adding a `devcontainer.json` file for GitHub Codespaces

[cr2007]

With GitHub Codespaces new being available to all users with an extremely generous monthly limit, I wanted to suggest if it is possible to create a devcontainer directory for easily setting up the Developer Environment.

All the packages would be installed when the codespace is setup and the developer can get into the development part straightaway.

Things required:

• devcontainer.json - Lists all the features of the container in order to setup the required settings (extensions, libraries, image,etc.)
  • Even a Dockerfile works as well if there is an appropriate one.

[Akilan1999]

We would only want to use Github to store the repo. The fancy features are not needed.