This PR changes metrics collection to actually measure the time interval between collections, rather
than assume 3 seconds. I did some ad hoc profiling, and on slower hardware (eg, my Raspberry Pi 4)
I routinely saw intervals between 3.3 - 3.5 seconds, with some being as high as 4.5 seconds. This
will generally cause the CPU gauge readings to be too high, and in some cases can cause impossibly
large values for the CPU load metrics (eg. greater than 400 for a 4 core CPU).
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Co-authored-by: Felix Lange <fjl@twurst.com>
* replace gosigar with gopsutil
* removed check for whether GOOS is openbsd
* removed accidental import of runtime
* potential fix for difference in units between gosig and gopsutil
* fixed lint error
* remove multiplication factor
* uses cpu.ClocksPerSec as the multiplication factor
* changed dependency from shirou to renaynay (#20)
* updated dep
* switching back from using renaynay fork to using upstream as PRs were merged on upstream
* removed empty line
* optimized imports
* tidied go mod
