chore(package): update karma to version 1.7.1

Closes #24

Author: greenkeeper[bot]

package.json

@@ -68,7 +68,7 @@
     "http-server": "0.9.0",
     "istanbul": "^0.4.5",
     "jshint": "^2.9.4",
-    "karma": "1.5.0",
+    "karma": "1.7.1",
     "karma-coverage": "^1.1.1",
     "karma-mocha": "^1.3.0",
     "karma-phantomjs-launcher": "1.0.4",