Add ability to "Log Out" of Custom Auth

Now that I have "Log In" working via Custom Auth, I want to give my users the ability to "Log Out". This would entail clearing the magic variables stored within the Custom Auth flow on the resource. I've consulted with Support and they inform me that this isn't possible today...and suggested I should file a Feature Request. So here it is!

Feature Request: Ability to clear magic variables stored by Custom Auth flow.