openidconnect: Account info auto-update

[mmattel]

WHAT Needs to be Documented?

References: owncloud/openidconnect#222 (Account info auto-update)

When merged, a new functionality is added that needs documentation in the config.apps sample documentation that will finally end up in https://doc.owncloud.com/server/10.10/admin_manual/configuration/server/config_apps_sample_php_parameters.html#app-openid-connect-oidc

Note that post merging those changes in core, we need to do a config-to-docs run in docs to transport the changes to docs.

This PR is the doc central point for this change and all PR's necessary will be referenced here.

WHERE Does This Need To Be Documented (Link)?

The change is needed to be done in core !! as config.sample files are origined in master.

WHY Should This Change Be Made?

(Optional) What Type Of Content Change Is This?

• New Content Addition
• Old Content Deprecation
• Existing Content Simplification
• Bug Fix to Existing Content

(Optional) Which Manual Does This Relate To?

• Admin Manual
• Developer Manual
• User Manual
• Android
• iOS
• Branded Clients
• Desktop Client
• Other