ethjs-abi and ethjs-query are out-of-date #24

The ethjs-abi and ethjs-query dependencies are out-of-date. Please upgrade and deploy a new version to npm.

Examples of things that are broken

• ethjs-abi encodeSignature method does not exist yet.
• ethjs-query does not handle promise rejections correctly and results in UnhandledPromiseRejectionWarning exceptions. See Unhandled promise rejection on errors #21 as well.

Current workaround is to use the child libraries directly, but that defeats the purpose of having the parent ethjs library at all.