Eng 6095 index with address

Don't merge, only for review.

Pass eecheck on local machine, but haven't check the result of Junit test.

I worry about how to deconstruct Key and Data: is the default deconstructor enough?

After refining the code, the next step is to append address to KeyType other than IntsKey.
It would be a good idea to add an iteration step to this test that validated that all the expected tuples and only the expected tuples were deleted.