Added remote_api to app.yaml.

This enables the use of the command line tools for AppEngine, to e.g. pull the data items, provided that the user is an authenticated admin.

More details here: https://developers.google.com/appengine/docs/python/tools/uploadingdata

R=rnystrom@google.com

Review URL: https://chromiumcodereview.appspot.com//113653005