public BookStorage(string folderPath, SIL.IO.IChangeableFileLocator baseFileLocator,
BookRenamedEvent bookRenamedEvent, CollectionSettings collectionSettings)
{
_folderPath = folderPath;
//we clone becuase we'll be customizing this for use by just this book
_fileLocator = (IChangeableFileLocator) baseFileLocator.CloneAndCustomize(new string[]{});
_bookRenamedEvent = bookRenamedEvent;
_collectionSettings = collectionSettings;
ExpensiveInitialization();
}