replaced "keys" to "keywords" to correct npm keywords list

Author: unclechu

package.json

@@ -2,9 +2,9 @@
   "name": "deep-extend",
   "description": "Recursive object extending.",
   "license": "MIT",
-  "version": "0.3.1",
+  "version": "0.3.2",
   "homepage": "https://github.com/unclechu/node-deep-extend",
-  "tags": [
+  "keywords": [
     "deep-extend",
     "extend",
     "deep",