Re-implement fix for MB-35326, cleaner KVStore API changes

This MB is to track and improved version of the fix for MB-35326, the improved version is logically the same but we want to restructure some of the KVStore API to better hide the cache clearing.

The cleaned up fix will do the following.

1. rename KVStore::incrementRevision to KVStore:prepareToCreate
2. Follow the pattern of prepareToDelete and add a virtual prepareToCreateImpl
3. KVStore:prepareToCreate will do the cache reset
4. prepareToCreateImpl will do the same job as the current incrementRevision code