chore(package): update through2 to version 3.0.1

Closes #20

Author: greenkeeper[bot]

package.json

@@ -45,7 +45,7 @@
     "mocha": "*",
     "shelljs": "^0.7.5",
     "standard-version": "4.2.0",
-    "through2": "^2.0.3"
+    "through2": "^3.0.1"
   },
   "dependencies": {
     "compare-func": "^1.3.2",