mod_http_oauth2: Create proper template for OOB code delivery This also improves security by reusing the security and cache headers, where mod_http_errors/http-message doesn't add such headers. Colors selected by taking rotating the error colors, rrggbb -> ggbbrr

This module lets you block connections to remote servers at the s2s
level.

``` {.lua}
modules_enabled = {
    -- other modules --
    "s2s_blacklist",

}
s2s_blacklist = {
    "proxy.eu.jabber.org",
}
```