registration and authentication flow diagrams

Here's WebAuthn registration and authentication flow diagrams..

WebAuthn-Figures-00
https://docs.google.com/presentation/d/1om__oSew4n48MK_Qcc8deq6hCZ6720-Zvv1PdK0CrjA

..based on the present editor's draft.  I think they are mostly correct, tho review encouraged :)   especially by "platform folks".

thanks, HTH,

=JeffH