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 …