Add schema document for social-relay
Add schema document for social-relay

See https://wiki.diasporafoundation.org/Relay_servers_for_public_posts

jaywink/the-federation.info,Flaburgan/diaspora-hub,Flaburgan/the-federation.info,Flaburgan/diaspora-hub,jaywink/diaspora-hub,jaywink/diaspora-hub,Flaburgan/diaspora-hub,Flaburgan/the-federation.info,jaywink/the-federation.info,Flaburgan/the-federation.info,jaywink/diaspora-hub,jaywink/the-federation.info,Flaburgan/the-federation.info