Create docs website

### To do
- Create some website, basing on some popular static website tool like: mkdocs / just-the-docs / redocly / sth else.

### Requirements
- Easy maintenance
- Article based on markdown
- Adding new article and tab is easy and don't require coding
- It would be great to have nice main page with the best tradukisto's features and eye-pleasing
- https://squidfunk.github.io/mkdocs-material/ - looks nice