Include files clean up.
Dropping debug output.
Class decomposition.
More decomposition.
Code style.
Final function decomposition over `rotate` file.
Typo fix.
Local functional refactoring.
Extracting counting function.
Constness.
Tiny condition shuffling and variable renaming.
Renaming.
Minor renaming and class decomposition done over rollover pairs.
Rollover pair members renaming.
Checking strftime return value (but not doing anything yet).
Access modifier review.
Naming.
Rotator config are replaced into its own file.

Also `rotator` namespace is now called `rotation`.
Test fixture splitting.
Timer class is moved into its own file.