OS description is updated

The following chapters of the description were updated: Module executors — a new chapter was added; Platform coverage — the chapter was fully rewitten; Sivelkiria OS mission — some changes were made to the chapter; Sivelkiria OS concepts – the chapter was translated to English; Example: image file viewer program – the chapter was translated to English.

Article chapters added: “Software development process” and “Plans and priorities”

There are two completely new chapters added to the introductory article on Sivelkiria OS: “Software development process” and “Plans and priorities”. Also, the following sections were updated and expanded: “Security”, “Disadvantages of proposed solution”, “Interacting with other systems” and “Platform coverage”. I am pleased to thank dear V. S. for his very useful feedback these …