mod_rest: Remove manual reference expansion in schema This hack was originally added to reduce the number of definitions of common attributes (type, to, from etc) and payloads (e.g. delay). This predated pointers and references, and until now was needed because parsing picked out the correct stanza kind from the schema, which broke internal references. Removing this hack paves the way for allowing the schema to be configured or customized more easily.

---
labels:
- 'Statistics'
...

This module publishes data from [Prosody's `internal` statistics][doc:statistics]
 into a PubSub node in [XEP-0039] format.

The node defaults to `stats` but can be changed with the option
`pubsub_stats_node`.

``` lua
Component "pubsub.example.com" "pubsub"
modules_enabled = {
    "pubsub_stats";
}
pubsub_stats_node = "statistics"
```