Also, fix some incorrect config names (rrd_step -> rrd.step)
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Allows ping checks at intervals not tied to the poller. Pointless if you are not alerting on device status.
I updated the rrdstep.php script to treat ping-perf files separately and made it so it only converts if needed.
Docs here: https://docs.librenms.org/Extensions/Fast-Ping-Check/
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* Fixed IPv6 host renaming
* Added get_rrd_dir() and modified other files to use it where appropriate.
* rrd_name() now uses the new function get_rrd_dir(), to make it simpler to modify the escaping in the future.
* Wrong function name in rrdstep.php
