read_packet.
(oop_timer_retry): New function.
(transport_start_read): Use oop_timer_retry to implement retrying.
(transport_write_pending): Split into two functions, ...
(transport_start_write, transport_stop_write): ... new functions.
(transport_send_packet): New argument flags. Let a NULL packet
imply a push of buffered data. Updated callers.

Rev: src/transport.c:1.6.2.9