Set up testing with live account

[aliang]

You could pass the Google Account you want to use and possibly password as environment variables, and it could run a test on Google's servers.

This is to protect against API changes on Google's end

[draffensperger]

I really like this idea! For my PR yesterday, I actually used my whole existing application to test it, would have been nice to have a micro test environment. No promises on a time frame, but I'd be happy to work on that next time I get a chance to do work on this gem.