This was used by the custom gas slider on the `send` screen, and it was used to modify the gas value before sending it out, breaking our new custom gas field logic.
Removed it and the logic that referred to this now-outdated parameter.
These external modules now have their own test coverage and build enforcement. This allowed me to somewhat more easily add good tests around our personalSign strategy (held now in [eth-sig-util](https://github.com/flyswatter/eth-sig-util), and allow each of the keyrings to import that, etc.
removed unnecessary this.query = opts.query from constructor
Created a tx error state for errors in approveTransaction
validateTxParams has been moved to tx-utils
removed "value" arg from _setTxStatus
