Adding cover-es6

So I can see if the lines actually match my es6 files on coverall

package.json

@@ -6,6 +6,7 @@
   "scripts": {
     "test": "mocha --compilers js:babel/register spec/",
     "cover": "istanbul cover node_modules/mocha/bin/_mocha --report lcovonly -- --compilers js:babel/register --colors --reporter spec spec/",
+    "cover-es6": " node --harmony node_modules/istanbul-harmony/lib/cli.js cover --print both --hook-run-in-context  node_modules/mocha/bin/_mocha -- -R spec --U exports --compilers js:babel/register spec/",
     "lint": "npm run lint:lib && npm run lint:src&& npm run lint:spec",
     "lint:spec": "jshint spec/",
     "lint:lib": "jshint lib/",
@@ -14,7 +15,7 @@
     "compile:src": "babel -d compiled/dist/ src/",
     "compile:libs": "babel -d compiled/lib/ lib/",
     "prepublish": "npm run compile",
-    "build": "npm run lint && npm run test && npm run cover",
+    "build": "npm run lint && npm run test && npm run cover-es6",
     "post-build": "rm -rf coverage/"
   },
   "repository": {
@@ -36,6 +37,7 @@
     "babel": "^5.8.23",
     "coveralls": "^2.11.4",
     "istanbul": "^0.4.0",
+    "istanbul-harmony": "^0.3.16",
     "jshint": "^2.8.0",
     "mocha": "^2.3.3"
   }