Ideas
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+- track devices:
+ - alert when never before seen device is plugged-in
+ - report history and trends on when and how-often each
+ device/category is plugged-in, how-long it stays plaugged-in, etc.
- daemonize `khatus`, so we don't have to re-launch `X11` to re-launch `khatus`
- interoperate with other khatus instances
- prefix machine ID to each data source