Update PostCSS

Author: ai

package.json

@@ -10,7 +10,7 @@
     "postcss-load-config": "^1.0.0",
     "object-assign":       "^4.1.0",
     "loader-utils":        "^0.2.16",
-    "postcss":             "^5.2.4"
+    "postcss":             "^5.2.5"
   },
   "devDependencies": {
     "eslint-config-postcss": "2.0.2",