mod_pubsub_serverinfo: Update to use mod_server_info (fixes #1841)
...but only for Prosody trunk users, because 0.12 mod_server_contact_info does
not use the new API in mod_server_info.
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summary: Extra verbose logging of sent and received
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Summary
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Sometimes it is useful to get the raw XML logs from clients for
debugging purposes, but some clients don't expose this.
This module logs dumps everything sent and received into debug logs, for
debugging purposes.