v0.4.0

What's Changed

• Add a CodeCarbon exercice. by @esclapez in #27
• Add and refactor content - incorporate Ben and Ireen's suggestions by @raar1 in #45
• Populate about.md by @esclapez in #48
• Add storage energy usage slide by @esclapez in #50
• Move to NEBULA 1.2.2 by @raar1 in #51

Full Changelog: v0.3.0...v0.4.0