- vlc_dialog_wait_question will replace dialog_Question

- vlc_dialog_wait_question with i_type == VLC_DIALOG_QUESTION_CRITICAL and
  without action1/action2 will replace dialog_FatalWait

- vlc_dialog_wait_login will replace dialog_Login

- vlc_dialog_display_progress will replace dialog_Progress

- dialog_Fatal is replaced by vlc_dialog_display_error

- vlc_dialog_display_error will replace dialog_Fatal

- vlc_ext_dialog_update will repalace dialog_ExtensionUpdate

- vlc_dialog_wait_question and vlc_dialog_wait_login are interruptible via
  vlc_interrupt.

- Nothing prevents to have more than one dialog type displayed at a time.