(try_password_auth): Use interact_read_password.
(send_userauth_info_response): Use interact_dialog.
(read_user_key): Updated for alist_select_l change.
(OPT_ASKPASS): New constant. Use an enum for all the options constants.
(main_options): Added --askpass option.
(main_argp_parser): Use interact_set_askpass.
(main): Use unix_interact_init.

Rev: src/lsh-transport.c:1.13