mod_pubsub_serverinfo: Detect existence of pub/sub node Instead of blindly trying to create the pub/sub node to publish items to, a service discovery query is performed to check if node creation is required. Added various bits of warn and debug logging, to give a user better feedback if and why something is failing.

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summary: Storage benchmark tool
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To benchmark `mod_storage_internal`:

    prosodyctl mod_benchmark_storage internal

Does a number (aprox. 10000) of reads and writes and to the selected
storage driver and tells you how long it took.