Added ENUM roots: enumer+nrenum, deleted dead e164.org

[maxihatop]

I updated ENUM roots:

• Deleted out-of-service e164.org
• Added two actual working ENUM roots: a) ENUMER - decentralized blockchain-based ENUM: http://enumer.org/ b) Nrenum - ENUM services for academia: https://nrenum.net/

ENUMER architecture described here: https://medium.com/@emer.tech/voip-made-free-with-blockchain-introducing-enumer-35235c4abec5