[gdm] (10 commits) Created branch wip/multi-stack

[Ray Strode <halfline src gnome org>]

The branch 'wip/multi-stack' was created.

Summary of new commits:

  f341bdf... greeter: drop is-interactive stuff
  4a9dc64... daemon: Make current pam conversation explicit throughout c
  9b5fb15... daemon: Rename session worker to the service it's managing
  6d7ead4... daemon,greeter: Make greeter/autologin session initiate PAM
  c0cf573... daemon: Store multiple conversations in the session
  2fb8d96... daemon: Distinguish "pam module failed" from "authenticatio
  3faf619... greeter: Add a login extension mechanism to greeter
  a1630fa... greeter: Add fingerprint plugin
  091bcf1... greeter: Add smartcard plugin
  45654e9... doc: mention new split authentication feature