Allow PChannel::Unavailable, indicating a ICMP error in UDP transmit, to be passed up when reading from a socket bundle. Also added extra trace logs.
Applied patch #230 "Fix for bug #433", thanks Valeriy V. Argunov
Fixed bug #432 "Assertion fails when PServiceProcess can't be started."

Do not do PSystemLog output when PProcess not valid, either before construction or after destruction.