Points to ians css-color-func 1.3.1 tag

Author: tylergaw

package.json

@@ -17,7 +17,7 @@
     "index.js"
   ],
   "dependencies": {
-    "css-color-function": "tylergaw/css-color-function.git#tg-ignore-alpha-on-mix",
+    "css-color-function": "ianstormtaylor/css-color-function.git#1.3.1",
     "postcss": "^5.0.4",
     "postcss-message-helpers": "^2.0.0",
     "postcss-value-parser": "^3.3.0"