Resolve "Implement endpoints for FreeRADIUS rlm_rest"

This MR adds endpoints for FreeRADIUS' rlm_rest module, for authorization and accounting.

To configure:

1. Install freeradius-rest
2. Enable module in mods-enabled
3. Add rest into the blocks accounting and authorize in default and inner-tunnel
4. Configure rest module as follows

        connect_uri = "https://sis.example.com"

        authorize {
                uri = "${..connect_uri}/app/kompjuter/api/radius/auth/"
                method = 'post'
                body = 'json'
                auth = 'basic'
                username = 'client_id'
                password = 'client_secret'
                tls = ${..tls}
        }

        accounting {
                uri = "${..connect_uri}/app/kompjuter/api/radius/acct/"
                method = 'post'
                body = 'json'
                auth = 'basic'
                username = 'client_id'
                password = 'client_secret'
                tls = ${..tls}
        }

Closes #9 (closed)