Provide an option to log unix timestamp as well

Currently, the intervals configuration are set to log every x seconds and the output starts from 1 making it fit for most cases.

It would be great to have another configuration flag that would log results with the current unix timestamp. I can send a PR from my fork actually if people are interested in this.

No file, test, or entry point is named. Start by locating the intervals configuration and the code that produces logged CPU and memory results; determine how a Unix-timestamp option should affect the output, then verify that enabled logging uses current Unix timestamps while existing interval behavior remains unchanged.

Written by the indexing model from the issue text.