docker-microbit-toolchain

• Move from Ubuntu 18.04 to 20.04
• Update Arm GCC to v10.2.1
• Improved how python3 is configured as the default python
  Full Changelog: https://github.com/carlosperate/docker-microbit-toolchain/compare/v1.0.0...v2.0.0

Common Docker image

• Reduce docker image size by removing package install caches
• Better documentation

Devcontainer

• Set zsh as the default devcontainer shell
• Set up the default user to vscode (non-root)
• Add useful C++ extensions to VSCode

Full Changelog: https://github.com/carlosperate/docker-microbit-toolchain/compare/0.3.1...v1.0.0

Fixes issue building the right image for the devcontainer.

Rename ubit to microbit.

Adding a Codespaces devcontainer.

Basic image.