Пакет 3proxy: Информация

- drop some config options while rewrite droproot patch (see README.ALT)
- use capabilities when root is dropped (closes: #18060)
- use _3proxy as default user (closes: #11942)

- new version (closes: #20198).
- adopt droproot code to new version.
- move droproot code into droproot patch.
- move minor change into alt-changes patch.

- add README-ALT.*
- set default user to root untill #11942 be fixed