title: Phone number based auth in Firebase (with Digits)
body: <p>I am super impressed with the new Firebase and auth options in that. But what if I want to create my own userID-password system to create a user? Like for example I authenticate the user with his phone number (using something like Fabric's Digits) and use that to create an user account. Now, how can I do this in the new Google's firebase? Or is it even doable?</p>