mod_http_oauth2: Implement RFC 7628 Proof Key for Code Exchange Likely to become mandatory in OAuth 2.1. Backwards compatible since the default 'plain' verifier would compare nil with nil if the relevant parameters are left out.

---
labels:
- Stage-Alpha
rockspec:
  dependencies:
  - mod_sasl2
summary: "XEP-0386: Bind 2.0"
---

Experimental early implementation of [XEP-0386: Bind 2.0] for use with
[mod_sasl2].