Add ember-cli-update.

Author: chriskrycho

package.json

@@ -56,6 +56,7 @@
     "ember-cli-shims": "^1.1.0",
     "ember-cli-sri": "^2.1.0",
     "ember-cli-uglify": "^1.2.0",
+    "ember-cli-update": "^0.13.2",
     "ember-disable-prototype-extensions": "^1.1.2",
     "ember-export-application-global": "^2.0.0",
     "ember-load-initializers": "^1.0.0",