this includes:
 - refactoring existing logic so that it uses the incrementalCache class
   concept that Next.js also uses (so that we alight the two implementations)
 - reading the user next.config.(m)js file and create a custom cache
   handler and collecting the cache handler referenced in the
   incrementalCacheHandlerPath config
 - building the custom cache handler instead of the built-in ones in case one was
   indeed provided by the user