message: Require superagent without es6 import
diff: // Copyright 2014, BitGo, Inc. All Rights Reserved.
  //
  -import superagent = require('superagent');
  +const superagent = require('superagent');
  import bitcoin = require('./bitcoin');
  import bitcoinMessage = require('bitcoinjs-message');
  import sanitizeHtml = require('sanitize-html');
  