mod_rest/rest.sh: Update to use httpie-oauth2 plugin This bash implementation of OAuth2/OIDC was growing to the point where it needed a massive refactor, which made me look into alternatives where I finally settled on implementing oauth2 in a plugin for HTTPie.

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",
}
```