TRANSPORT_EVENT_PUSH, check that service_writer is non-NULL.
(make_lsh_transport_connection): Initialize service_reader and
service_writer to NULL.
(oop_read_service, oop_write_service): New functions.
(lsh_transport_service_start_read)
(lsh_transport_service_stop_read)
(lsh_transport_service_start_write)
(lsh_transport_service_stop_write): Implemented.
(lsh_transport_packet_handler): Verbose message for
USERAUTH_SUCCESS. Don't try to display the message list for
USERAUTH_FAILURE.
(start_service): Initialize service_reader and service_writer, and
start reading.
(lsh_transport_lookup_verifier): Fixed handling of capture_fd.

Rev: src/lsh-transport.c:1.1.2.7