added _missingSequenceNumbers tracking to OctreeInboundPacketProcessor
added code for AC to send nack packets; no locking yet
added locking on _singleSenderStats; untested!
Revert "added locking on _singleSenderStats; untested!"

This reverts commit c542da97076ba0d27f4e191ae5d8249dbf8afe7e.
Revert "added code for AC to send nack packets; no locking yet"

This reverts commit 15bd0878c407ede95f724009adadc81deeb7b4fd.
rollovers are now handled in SingleSenderStats::trackInboundPacket
added sendNackPackets() to OctreeInboundPacketProcessor

added rollover handling in _missingSequenceNumbers pruning; added
EditNack packet types; added getMyEditNackType() to OctreeServer
subclasses; added code to randomly skip edit packet sequence numbers for
testing in OctreeEditPacketSender
added OctreeInboundPacketProcessor::process() override to send nack periodically

added code to remove dead nodes' stats in sendNackPackets()
minor changes before moving SentPacketHistory
moved SentPacketHistory to libraries/networking/src
removed old SentPacketHistory
added code to parse nack packets in OctreeEditPacketSender
SentPacketHistory now handles rollover

updated SentPacketHistory path in comments
removed magic number 65536 from OctreeInboundPacketProcessor
changed OctreeEditPacketSender to queue packets for resend as nack is parsed
added processNackPacket calls to DatagramProcessor
forgot to add "break;"s
edit nacks ready for test; seq numbers sometimes repeat??
edit nacks seem to be working;

added mutex for releaseQueuedPacket() to prevent duplicate packets being
queued up due to the steps of queueing the packet and clearing it not
being atomic.
added OctreeEditPacketSender::nodeKilled(), no locks yet

also added nodeKilled() calls to the 3 editsenders in
Application::nodeKilled()