[FEATURE REQUEST] Finalise UN Official languages

[darigovresearch]

Would be good to get the UN official languages translated as it would cover a large variety of the global population, see below for the relevant issues

• [ ] Arabic (Modern Standard Arabic) - https://github.com/darigovresearch/Intro-to-DIY-Off-Grid-Systems/issues/18
• [ ] Chinese (Mandarin Chinese in simplified Chinese characters) - https://github.com/darigovresearch/Intro-to-DIY-Off-Grid-Systems/issues/19
• [x] English
• [ ] French - https://github.com/darigovresearch/Intro-to-DIY-Off-Grid-Systems/issues/6
• [ ] Russian - https://github.com/darigovresearch/Intro-to-DIY-Off-Grid-Systems/issues/14
• [ ] Spanish - https://github.com/darigovresearch/Intro-to-DIY-Off-Grid-Systems/issues/5