Provide ability for custom model mismatch handling

Forgive me because I don't claim to know the full repercussions of attacking my need this way. Instead of using `shouldDeleteStoreOnModelMismatch` to flag an automatic reset of the data store, I have written my own code to reset the file, but I have no way of easily being notified if the store is out of sync without some sort of error handling. Moving the `handleErrors` message call out of the if block seems to be the best solution for my situation.
If anyone knows of a better way please let me know.