Add a function/config to proxy sites that restrict access on their own

[Erghel]

Collect a database of sites that restrict access for users themselves.

[meetinger]

In most cases, these are sites with a domain that ends in ".ua"

[zloirock]

@meetinger you are deluded.

[Erghel]

During all this time we have managed to collect a small register of sites, you can check yourself with it here - https://github.com/roskomsvoboda/ctconf/blob/main/reverse-restrictions/ru/sites.json