This change enables log rotation, which can be activated using the flag --log.rotate. Additional parameters that can be given are: 

  - log.maxsize to set maximum size before files are rotated,
  - log.maxbackups to set how many files are retailed, 
  - log.maxage to configure max age of rotated files, 
  - log.compress whether to compress rotated files

The way to configure location of the logfile(s) is left unchanged, via the `log.logfile` parameter.  

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Co-authored-by: Martin Holst Swende <martin@swende.se>