Consider exposing claims for username, email, phone etc in id_token in a more user friendly way

[roxk]

Currently there is no way to obtain username/email/phone after obtaining the refresh token. User info also doesn't expose these information (there is only isAnonymous, isVerified and sub now). Consider adding these info in userinfo, or implementing extracting username/email/phone in id_token's claims.

Things to consider:

• Username/email/phone might each be optional
• Additional data bundled together with each authenticator (e.g. phone might come with 852? Just an example)

[fungc-io]

depends on authgear/authgear-server#260