chore(package.json): use devDependencies instead of dependencies

Author: dankohn

package.json

@@ -1,7 +1,7 @@
 {
   "name": "AngularJS",
   "version": "0.0.0",
-  "dependencies": {
+  "devDependencies": {
     "grunt": "0.4.0",
     "grunt-contrib-clean": "0.4.0",
     "grunt-contrib-compress": "0.4.1",