Typo in code


#1

The documentation contains the wrong url,
the 2015 is wrong, should be 2016.
https://eprint.iacr.org/2015/889.pdf is "Which Ring Based Somewhat Homomorphic Encryption Scheme is Best?"
and
https://eprint.iacr.org/2016/889.pdf is “Ouroboros: A Provably Secure Proof-of-Stake Blockchain Protocol”