It now supports custom conversation methods, so instead of
new() we ask for a default authenticator taking a password
via with_password(). Since the password is now handled by
the now separate conversation handler, `set_credentials()`
is now called on the handler we get via `.get_handler()`.
Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
1d77b6cf6b