title: Single Logout with OIDC
body: <p>I am working on an Idp customization. I need to have it handle a Single Logout request from an SP that had logged in with OIDC.
  I currently have the Single Logout functionality for SAML, but I the client has requested for OIDC as well. 
  Is there a standard industry method of sending a Single Logout request? What does a typical SP send to the Single Logout endpoint?</p>