Properly remove Babel.

package.json

@@ -37,11 +37,6 @@
     "truffle-hdwallet-provider": "0.0.3"
   },
   "devDependencies": {
-    "babel-polyfill": "6.26.0",
-    "babel-preset-es2015": "6.24.1",
-    "babel-preset-stage-2": "6.24.1",
-    "babel-preset-stage-3": "6.24.1",
-    "babel-register": "6.26.0",
     "eslint": "4.13.1",
     "eslint-config-airbnb": "16.1.0",
     "eslint-plugin-import": "2.8.0",

truffle.js

@@ -1,7 +1,5 @@
 const HDWalletProvider = require('truffle-hdwallet-provider')
 const fs = require('fs')
-require('babel-register')
-require('babel-polyfill')
 
 // First read in the secrets.json to get our mnemonic
 let secrets