Allow users to authenticate via ORCID
Building on work that @jure has done previously in pubsweet-components@master...orcid-oauth
A user should be allowed to sign up (or sign in, if they've already signed up) via ORCID.
As the ORCID API doesn't return email addresses of the authenticated user, if an existing user isn't found with the given ORCID ID the user will be asked to enter their email address. As an email address can only be attached to one user, if the email address is already associated with an existing account the user will need to sign into that existing account (using email address and password) before continuing with the ORCID authentication.