More hacks to work around a known bug in Cryptlib SSH...
"Sometimes" the write timeout value is used for read timeouts. Since we use a read timeout of zero, and a mutex, this can cause some serious delays in SSH processing. As a workaround, we set the write timeout to zero. However, a flush failure has historically been fatal. So, we now change the write timeout to one second just before a flush, and have a flush timeout not be fatal anymore... we set it back to zero after the flush. The fiddling with the write timouts will be removed once the bug is fixed, but the flush timout not being fatal may stay forever... add some comments to remind us to remove the hack in the future.