REST is already enabled on moodle.net but for authorised users only.

For xmlrpc there is a special treatment 'wstoken'=>'publichub' that logs user in as "public_hub"

This issue adds the same workaround for REST so we can have the same endpoint for both xmlrpc and rest requests to moodle.net

If parameter 'moodlewsrestformat' is specified, this endpoint will engage REST server, otherwise XMLRPC

https://moodle.net/local/hub/webservice/webservices.php
https://moodle.net/local/hub/webservice/webservices.php?moodlewsrestformat=json

Second part of this issue is to add hub_get_info in the list of WS functions available for public pseudo-user. This will allow us to retrieve information about downloadable courses without going to hubdirectory

Note, role "Public user" should have capability local/hub:viewsmallinfo