Updated the UDP stream test to report on the different periods of lost
and received packets during the test, to show how any lost packets were
distributed (bursty, random, etc).

Updated the messaging to now include result packets to retrieve results
from the remote endpoint. These are combined with the local result set
so that results are reported for both test directions.

Lots of small fixes to make sure that the right things are happening -
packet sizes are correctly calculated, sockets are closed appropriately,
memory is tidied up.