Figure out how to write the GENADDR function

[psivesely]

This function is only loosely described in the "Mitigating Multi-Target Attacks in Hash-based Signatures" scheme, and the reference implementation diverges significantly from what's described in the paper.

• See if I can "reverse-engineer" the logic used in the reference implementation.
• If still not sure, contact the authors.
• Make sure either way that the implementation stays suitable for a standalone implementation and is not integrated with XMSS-T.