devcontainers are a convenient way to provide users a reproducible
build environment. It is currently supported by Visual Studio Code,
Visual Studio and IntelliJ.
When the user opens the verilator repo in VSCode with the standard
devcontainer extension installed, VSCode will ask the user if they
want to reopen in the devcontainer, then build the Docker image as per
our definition and then restart VSCode 'remotely' attached to the
Docker container.
More information:
https://code.visualstudio.com/docs/devcontainers/containers
Also:
- zlibc is missing on Debian-based systems now
- Add non-root user to Dockerfile and make default
