can check if the current version has a known vulnerability, with the option to panic and exit if so, and otherwise show a warning in the controlpanel for admins
---------
Co-authored-by: ed <s@ocv.me>
reduce the overhead of function-calls from the client thread
to the svchub singletons (up2k, thumbs, metrics) down to 14%
and optimize up2k chunk-receiver to spend 5x less time bookkeeping
which restores up2k performance to before introducing incoming-ETA
use sigmasks to block SIGINT, SIGTERM, SIGUSR1 from all other threads
also initiate shutdown by calling sighandler directly,
in case this misses anything and that is still unreliable
(discovered by `--exit=idx` being noop once in a blue moon)
* slightly faster startup / shutdown
* forgot a jinja2 golf
* waste 4KiB changing prismjs back to gz since brotli is https-gated ;_;
* broke support for firefox<52 (non-var functions must be toplevel
or immediately within another function), now even firefox 10 /
centos 6 is somewhat supported again