commenting on the params

as with our [android quickstart](https://github.com/aerogear/aerogear-push-quickstarts/blob/master/client/contacts-mobile-android-client/src/org/jboss/aerogear/unifiedpush/quickstart/Constants.java#L21) demo, let's add comments on the params 
I would rather use 'creating' instead of 'registering' because 'registering' is what we do for the device WDYT?