Synchronet now requires the libarchive development package (e.g. libarchive-dev on Debian-based Linux distros, libarchive.org for more info) to build successfully.

Fix newly-introduced memory leak...

I was going to start keeping the old rect around again, but that
idea didn't pan out.  This massive memory leak is what I get for
not doing more commits while tuning.
14 jobs for master in 8 minutes and 43 seconds (queued for 12 seconds)
Status Job ID Name Coverage
  Build
passed #24538
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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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sexpots-freebsd

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sexpots-linux

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sexpots-windows

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syncdraw-freebsd

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syncdraw-linux

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syncterm-freebsd

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syncterm-linux

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syncterm-windows

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