fix: 增加node-sass依赖。

Author: cpselvis

package.json

@@ -1,6 +1,6 @@
 {
   "name": "builder-webpack3",
-  "version": "0.3.11",
+  "version": "0.3.12",
   "description": "webpack项目构建器.",
   "main": "lib/index.js",
   "scripts": {
@@ -13,7 +13,7 @@
     "url": "https://github.com/iv-web/builder-webpack"
   },
   "configs": {
-    "compatibleVersion": ">=0.3.9"
+    "compatibleVersion": ">=0.3.12"
   },
   "keywords": [
     "webpack",
@@ -37,6 +37,7 @@
     "html-webpack-externals-plugin": "^3.6.0",
     "html-webpack-inline-source-plugin": "0.0.9",
     "html-webpack-plugin": "^2.30.1",
+    "node-sass": "^4.9.0",
     "offline-webpack-plugin": "^0.0.3",
     "osenv": "^0.1.5",
     "px2rem-loader": "^0.1.7",