rem: BPlusTree::Insert(Transaction &transaction, uint64 key, off_t value)
add: BPlusTree::Insert(Transaction &transaction, const char *key, off_t value)
context: BPlusTree::Insert(Transaction &transaction, uint64 key, off_t value){	if (fHeader->data_type != BPLUSTREE_UINT64_TYPE)		return B_BAD_TYPE;	return Insert(transaction, (uint8 *)&key, sizeof(key), value);}