fix: move webpack about loader and plugins to devDependences

package.json

     "@fortawesome/fontawesome-svg-core": "^1.2.4",
     "@fortawesome/free-solid-svg-icons": "^5.3.1",
     "@fortawesome/react-fontawesome": "^0.1.3",
+    "braft-editor": "^2.0.5",
+    "object-assign": "4.1.1",
+    "promise": "8.0.1",
+    "raf": "3.4.0",
+    "react": "^16.5.0",
+    "react-dom": "^16.5.0",
+    "react-mde": "^5.8.0",
+    "resolve": "1.6.0",
+    "showdown": "^1.8.6",
+    "whatwg-fetch": "2.0.3"
+  },
+  "devDependencies": {
     "autoprefixer": "7.1.6",
     "babel-cli": "^6.26.0",
     "babel-core": "6.26.0",
     "babel-preset-react": "^6.24.1",
     "babel-preset-react-app": "^3.1.2",
     "babel-runtime": "6.26.0",
-    "braft-editor": "^2.0.5",
     "case-sensitive-paths-webpack-plugin": "2.1.1",
     "chalk": "1.1.3",
     "css-loader": "0.28.7",
     "fs-extra": "3.0.1",
     "html-webpack-plugin": "2.29.0",
     "jest": "20.0.4",
-    "object-assign": "4.1.1",
     "postcss-flexbugs-fixes": "3.2.0",
     "postcss-loader": "2.0.8",
-    "promise": "8.0.1",
-    "raf": "3.4.0",
-    "react": "^16.5.0",
     "react-dev-utils": "^5.0.2",
-    "react-dom": "^16.5.0",
-    "react-mde": "^5.8.0",
-    "resolve": "1.6.0",
-    "showdown": "^1.8.6",
     "style-loader": "0.19.0",
     "sw-precache-webpack-plugin": "0.11.4",
     "url-loader": "0.6.2",
     "webpack": "3.8.1",
     "webpack-dev-server": "2.11.3",
-    "webpack-manifest-plugin": "1.3.2",
-    "whatwg-fetch": "2.0.3"
+    "webpack-manifest-plugin": "1.3.2"
   },
   "scripts": {
     "start": "node scripts/start.js",