Translate into English

[bespoyasov]

Make the book accessible to the English-speaking audience:

• [ ] Translate the content;
• [ ] Split content by the locales;
• [ ] Set up the routing system considering the locale;
• [ ] Create a locale toggle in the UI;
• [ ] Update the PDF builder to consider the locale;
• [ ] Set up the build and deployment;
• [ ] Swap the project description in Readme and docs.