chore(build): upgrade build dependencies

.babelrc

@@ -1,5 +1,5 @@
 {
-  "presets": ["env", "stage-3"],
+  "presets": ["@babel/preset-env"],
-  "plugins": ["transform-runtime"],
+  "plugins": ["@babel/plugin-transform-runtime"],
   "ignore": []
 }

package.json

@@ -11,23 +11,22 @@
   "author": "ahonn, olOwOlo",
   "license": "MIT",
   "devDependencies": {
-    "assets-webpack-plugin": "^3.8.4",
+    "@babel/core": "^7.1.2",
-    "autoprefixer": "^8.6.5",
+    "@babel/plugin-transform-runtime": "^7.1.0",
-    "babel-core": "^6.26.3",
+    "@babel/preset-env": "^7.1.0",
-    "babel-loader": "^7.1.5",
+    "assets-webpack-plugin": "^3.9.7",
-    "babel-plugin-transform-runtime": "^6.23.0",
+    "autoprefixer": "^9.3.1",
-    "babel-preset-env": "^1.7.0",
+    "babel-loader": "^8.0.4",
-    "babel-preset-stage-3": "^6.24.1",
     "clean-webpack-plugin": "^0.1.19",
-    "css-loader": "^1.0.0",
+    "css-loader": "^1.0.1",
-    "file-loader": "^1.1.11",
+    "file-loader": "^2.0.0",
-    "mini-css-extract-plugin": "^0.4.1",
+    "mini-css-extract-plugin": "^0.4.4",
-    "node-sass": "^4.9.2",
+    "node-sass": "^4.10.0",
-    "optimize-css-assets-webpack-plugin": "^4.0.3",
+    "optimize-css-assets-webpack-plugin": "^5.0.1",
-    "postcss-loader": "^2.1.5",
+    "postcss-loader": "^3.0.0",
-    "sass-loader": "^7.0.3",
+    "sass-loader": "^7.1.0",
-    "uglifyjs-webpack-plugin": "^1.2.7",
+    "uglifyjs-webpack-plugin": "^2.0.1",
-    "webpack": "^4.15.1",
+    "webpack": "^4.25.0",
-    "webpack-cli": "^3.0.8"
+    "webpack-cli": "^3.1.2"
   }
 }