mod_rest: Expand mapping of XEP-0045 join stanza The previous 'join' mapping was apparently lost in translation when swithing to datamapper, so might as well map some properties allowing history control. Usually you probably want either zero history or history since the last known time of being joined. Maybe that the former should be the default?

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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.