chore(package): update dependencies

Author: greenkeeper[bot]

package.json

@@ -19,12 +19,12 @@
   },
   "devDependencies": {
     "babel-core": "^6.23.1",
-    "babel-loader": "^7.1.2",
+    "babel-loader": "^8.0.4",
     "babel-preset-react": "^6.23.0",
     "babel-preset-stage-2": "^6.22.0",
-    "react-hot-loader": "^3.1.3",
-    "webpack": "^3.10.0",
-    "webpack-dev-server": "^2.4.1"
+    "react-hot-loader": "^4.3.11",
+    "webpack": "^4.22.0",
+    "webpack-dev-server": "^3.1.10"
   },
   "dependencies": {
     "babel-preset-env": "^1.6.1",