0.16.11 -> 0.17.0

Before

Class WeiConverter was refering to raw values in atomic units native to blockchain as "Wei" in its name and members.

After

WeiConverter was renamed to Elympics.Util.RawCoinConverter and its members use term "raw" instead of "Wei".

Why?

Wei is a term specific to ETH and that class is meant to handle all coins we support, so its naming should be coin agnostic.