mod_auth_external: Improve error handling when non-blocking mode used without libevent

mod_http_upload: Skip write if nothing expired when checking Reducing unnecessary IO is good.

mod_http_upload: Add hint about checking that the base URL is reachable

mod_http_upload: Make loud noise if storage path can't be created or doesn't exist

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

mod_vcard_muc: Factor out avatar hash retrieval into a function for easier reuse

mod_muc_occupant_id: Update XEP number (XEP-0421)

mod_map: Update example in README to reflect recent changes

mod_map: Include last body text Body, timestamp and message count allows showing modern conversation list UI without a full archive sync.

mod_map: Include timestamps of first/last message (if reported) Allows ordering conversations by recent activity or oldest unread.