BSIP 64: Optional HTLC Preimage Length and Add Hash160 Algorithm

[jmjatlanta]

This BSIP will remove the requirement of a preimage length (making it optional), and adding an additional hash algorithm.

This PR fixes Issue #163

[xeroc]

I like the solution that sets the size to 0 to disable length check!

+1

[jmjatlanta]

@pmconrad I believe I addressed your concerns. Please review and let me know if you have anything else. Thanks!

[nathanielhourt]

I've written a hash160 implementation here, although I'd like to get some test data to ensure it is compliant with other implementations. Does anyone know of any test data or an easy-to-use hash160 tool?

[pmconrad]

@nathanhourt have you seen bitshares/bitshares-fc#143 ?

[nathanielhourt]

Ahh, nope.

[pmconrad]

How about including this change here #202:

Introducing this commonly used and known item for HTLC transaction as an optional feature is a very helpful step to satisfy the future of Cross Chain Swaps, parties involved within the Cross Chain Swaps will have to communicate their external addresses or some helpful references and info within the HTLC transaction upon creation.

[pmconrad]

Please specify that the memo field will be added as an extension to htlc_create_operation. This is sufficient to include it into the recipient's history, so there's no need to add it to the htlc_object.