fix(package): add webpack >= v4.0.0 (peerDependencies) (#84)

Author: michael-ciniawsky

package.json

@@ -74,6 +74,6 @@
     ]
   },
   "peerDependencies": {
-    "webpack": "^2.0.0 || ^3.0.0"
+    "webpack": "^2.0.0 || ^3.0.0 || ^4.0.0"
   }
 }