mod_http_oauth2: Declare additional client registration fields as strings Previously any property not listed in the schema was allowed in any form, which is probably a bit too liberal. Instead, limit extra fields to simple strings, which should still allow localized versions of the various URIs and descriptive properties per RFC 7591 §2.2

Introduction
============

This module turns Prosody hosts into components of other XMPP servers.

Configuration
=============

Example configuration:

``` {.lua}
VirtualHost "component.example.com"
modules_enabled = { "component_client" }
component_client = {
    host = "localhost";
    port = 5347;
    secret = "hunter2";
}
```