Add Google Sign-in

[kevin1015wang]

Sometimes, I like to switch browsers, but all of my progress is lost. It would be great if I could sync my data between devices/browsers. It doesn't have to be Google.

[csaye]

That's a cool idea, thanks Kevin! In the interest of collecting as little data as possible and keeping everything as open as possible, I'll probably hold off on auth for now, but definitely a good thing to keep in mind for the future