Get ERC20 contract decimals

[wtzb]

It doesn't appear that EthQL is capable of retrieving the decimal field of ERC20 contracts. The decimal field is a default field in ERC20, just like symbol and totalSupply, which EthQL does support. Would this be possible to implement?

[raulk]

@wtzb sure! Would you mind sending a pull request? It should be pretty straightforward. You can see how the totalSupply field is implemented, and do something similar.

[wtzb]

@raulk Sure thing 👍