Fix automatic log in on browser startup to handle delays in getting the config.json file

Although PR 184 works fine locally, when a remote server is introduced, it fails to log in. This is due to there being a delay in fetching the config.json file from the server. The cookie request from the social api code can be quite fast, so if there is any delay in getting the config file, then the tryPresenceSocket function fails as it hasn't got the necessary details.

This PR makes us handle both cases of the config.json being retrieved quickly or slowly.