Hello!

I'd like to add another mirror to the list. Please find the information 
below:

HTTP: http://mirror.docker.ru/centos/
HTTPS: https://mirror.docker.ru/centos/

Sync schedule: Every 3 hrs
Bandwidth: 2 Gbps
Location: Russia, St. Petersburg
Sponsor: docker.ru
Sponsor URL: https://docker.ru/
IPv4 address to authorize: 185.253.22.52
Mirroring AltArch: No

Thanks! Please let me know if I missed anything.