update npm packages.

Author: yama-dev

package.json

@@ -34,18 +34,20 @@
     "email": "tatsuya.yamamoto69@gmail.com"
   },
   "devDependencies": {
-    "@babel/cli": "^7.2.3",
-    "@babel/core": "^7.2.2",
+    "@babel/cli": "^7.4.4",
+    "@babel/core": "^7.4.5",
     "@babel/plugin-transform-object-assign": "^7.2.0",
-    "@babel/preset-env": "^7.3.1",
-    "babel-loader": "^8.0.5",
-    "browser-sync": "^2.23.6",
-    "eslint": "^5.12.0",
+    "@babel/preset-env": "^7.4.5",
+    "@babel/register": "^7.4.4",
+    "babel-loader": "^8.0.6",
+    "browser-sync": "^2.26.7",
+    "cross-env": "^5.2.0",
+    "eslint": "^5.16.0",
     "eslint-loader": "^2.1.1",
-    "mocha": "^5.2.0",
+    "mocha": "^6.1.4",
     "npm-run-all": "^4.1.2",
-    "webpack": "^4.28.4",
-    "webpack-cli": "^3.2.1"
+    "webpack": "^4.34.0",
+    "webpack-cli": "^3.3.4"
   },
   "dependencies": {
     "@yama-dev/js-dom": "0.0.6"