Switch to node sass because dart sass is slow af

Author: robneu

config/grunt/sass.js

@@ -1,5 +1,5 @@
 // https://github.com/sindresorhus/grunt-sass
-const sass = require( 'sass' );
+const sass = require( 'node-sass' );
 
 module.exports = {
 	options: {

package.json

@@ -42,6 +42,6 @@
     "grunt-wp-i18n": "1.x",
     "postcss-pxtorem": "4.x",
     "time-grunt": "1.x",
-    "sass": "1.x"
+    "node-sass": "4.x"
   }
 }