Clean interface of main wrap

[cbrzn]

The current interface of ethereum wrap can be simplified with the core building blocks to interact with ethereum. This means that currently we have methods like:

  callContractView(
    address: String!
    method: String!
    args: [String!]
    connection: Connection
  ): String!

  callContractStatic(
    address: String!
    method: String!
    args: [String!]
    options: TxOptions
    connection: Connection
  ): StaticTxResult!

  callContractMethod(
    address: String!
    method: String!
    args: [String!]
    options: TxOptions
    connection: Connection
  ): TxResponse!

  callContractMethodAndWait(
    address: String!
    method: String!
    args: [String!]
    options: TxOptions
    connection: Connection
  ): TxReceipt!

This is inspired by the previous ethereum plugin. We can improve this interface to just expose one method, and the different functionalities can be defined through arguments; for example, in this callContract* methods, we can create one and receive an option that can allow the method to wait or do a staticCall

Another example can be that we have sendTransaction & deployContract, we can expose the send method, and the user can do a deployment of a contract by defining the correct arguments