Add missing karma dependency.

Author: Jakobovski

package.json

@@ -10,6 +10,7 @@
   "devDependencies": {
     "grunt": "~0.4.4",
     "grunt-karma": "~0.8.2",
+    "karma": "~0.12.0",
     "grunt-contrib-jshint": "~0.10.0",
     "grunt-conventional-changelog": "~1.0.0",
     "jasmine-core": "~2.3.4",