Support for RaiBlocks

[robertohuertasm]

Coin name (XRB)

• link to logo: https://files.coinmarketcap.com/static/img/coins/32x32/raiblocks.png
• official website: https://raiblocks.net

Optional info (not mandatory, but saves me time):

• logo color (HEX): #xxxxxx
• bitcointalk.org thread:

[Jake0303]

We need this big time, Raiblocks is getting huge.