mod_sasl2: Further break up success handling, into pre/post stream:features This allows us to enable mod_smacks after sending success, but before sending stream:features. Previously, the features were being calculated before SM was finalized on the session. We can't finalize SM before sending <success> because it may generate stanzas.

---
summary: Store authentication events in the audit log
rockspec:
  dependencies:
  - mod_audit
...

This module stores authentication failures and authentication successes in the
audit log provided by `mod_audit`.