Sign in with Google

Added:

• Sign in with Google, on both the sign-in and sign-up pages. The first time creates your account and every time after signs you in, which is why the button says continue rather than either.
• If you already signed up with an email and password, using Google on that same address signs you into the account you already have. Your tokens, projects and history stay where they are — you do not end up with two accounts holding half your work each.