The following minor improvements were made to `README.md`:
- The notice about stable version was styled as block quote to emphasize
it more and it was moved right after the title of the section
"Versions", and a link to the production branch was added;
- versions table was updated to add links to branches for easier
navigation;
- some typos were fixed;
- wording was changed in couple of places to make it simpler;
- the `docker run` command was updated to:
- use long options to make it more self-explanatory;
- wrap password hash value placeholder in single quotes to avoid
variable expanding as password hashes tend to contain `$`;
- some other very minor changes to make `docker run` options uniform.
Co-authored-by: Philip H. <47042125+pheiduck@users.noreply.github.com>
