improvement: token decimals

[denverbaumgartner]

today: the repo only passes, expects, and utilizes the full uint representation of erc20, erc721, etc. token values. most people tend to like seeing these values converted to human-readable format at some point or another.

soon: at a bare minimum we will add in additional support to the ERC20 class for dealing with integer values. throughout the repo itself i'm not sure we should really do must as we should encourage best practice of dealing with values as integers to avoid precision errors or mistakes. within data aggregation & reporting 🔜 etc. this will be an obvious part of data cleaning & prep

[adamamsmith]

Closed by #26