Feature: Allow users to select their own review display name

[NickPriv]

1. We should stop writing authorID to the DB.
2. The first time someone creates a review or if the first thing they do is update their username, they should have an entry created in a user metadata collection that contains their chosen account name. Create a user metadata collection tied to google account ID.
3. We can default user names to their google name, and we will need to create a separate page to let the user update their user name if they want to. This will update an entry in a separate collection that contains user metadata.
4. Anytime we need to get user names, we need to query the collection that contains user account metadata to get the proper display name.