fix(deps): remove babel-core and babel call in wallaby. (#3044)

This change was originally added by @dignifiedquire, but mixed with other changes.

Author: johnjbarton

package.json

@@ -384,7 +384,6 @@
   },
   "devDependencies": {
     "LiveScript": "^1.3.0",
-    "babel-core": "^6.26.0",
     "browserify": "^14.5.0",
     "chai": "^4.1.2",
     "chai-as-promised": "^7.1.1",

wallaby.js

@@ -1,4 +1,3 @@
-const babel = require('babel-core')
 
 module.exports = function (wallaby) {
   return {
@@ -32,12 +31,6 @@ module.exports = function (wallaby) {
       'test/unit/**/*.spec.js'
     ],
 
-    compilers: {
-      '**/*.js': wallaby.compilers.babel({
-        babel: babel
-      })
-    },
-
     bootstrap: function (w) {
       var path = require('path')
       var mocha = w.testFramework