Initial support for offline message counting in msglist.js.

Added options:
 -count
 -all_subs
 -hide_zero

This allows this script to be used to create counts of messages in the groups.
Typical use: Stats on new messages in the last x days.
14 jobs for msglist-offline-stats-support in 9 minutes and 40 seconds (queued for 10 seconds)
Status Job ID Name Coverage
  Build
passed #31146
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jsdoor-freebsd

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jsdoor-linux

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jsdoor-windows

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sbbs-freebsd

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sbbs-linux

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sbbs-windows

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FreeBSD
sexpots-freebsd

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sexpots-linux

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sexpots-windows

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FreeBSD
syncdraw-freebsd

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syncdraw-linux

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syncterm-freebsd

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syncterm-linux

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passed #31143
FreeBSD
syncterm-windows

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