fix: path to index.js (#8)

Author: onigoetz

package.json

@@ -2,7 +2,7 @@
   "name": "postcss-modules-local-by-default",
   "version": "2.0.4",
   "description": "A CSS Modules transform to make local scope the default",
-  "main": "src/index.js",
+  "main": "index.js",
   "engines": {
     "node": ">= 6"
   },