How-to: Authenticate using OpenID Connect 1.0 authorization_code flow

[jgrandja]

Publish a guide on How-to: Authenticate using OpenID Connect 1.0 authorization_code flow

Related gh-499

[jgrandja]

Closing this as a duplicate of gh-538

NOTE: The demo-sample is configured with formLogin() and social login (Google), which both use OpenID Connect 1.0 authorization_code flow.