return false in packetVersionAndHashMatch on version mismatch
Merge pull request #2365 from birarda/master

fix for packet version mismatch
only output version mismatch once per sender per packet
fix bad startPosition in datagram unpack

The startPosition was wrong (too far back) and the bytesRead return
value was too big and the unpacking of the second chunk of the
datagram would start in the middle of the chunk.
Merge pull request #2371 from AndrewMeadows/master

fix bad startPosition in datagram unpack
Merge pull request #2363 from RyanDowne/master

removing fly to voxel option
Merge pull request #2368 from birarda/master

suppress constant packet version mismatch debug
increased head smoothing for visage