mod_vcard_muc: Add an alternative method of signaling avatar change When the avatar has been changed, a signal is sent that the room configuration has changed. Clients then do a disco#info query to find the SHA-1 of the new avatar. They can then fetch it as before, or not if they have it cached already. This is meant to be less disruptive than signaling via presence, which caused problems for some clients. If clients transition to the new method, the old one can eventually be removed. The namespace is made up while waiting for standardization. Otherwise it is very close to what's described in https://xmpp.org/extensions/inbox/muc-avatars.html

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summary: Presence deduplication module
labels:
- 'Stage-Alpha'
...

This module tries to squash incoming identical presence stanzas to save
some bandwidth at the cost of increased memory use.

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

  Option                         Type     Default
  ------------------------------ -------- ---------
  presence\_dedup\_cache\_size   number   `100`

The only setting controls how many presence stanzas *per session* are
kept in memory for comparing with incoming presenece.

Requires Prosody 0.10 or later.