don't change the socket buffer sizes if it is already larger
made JitterTester work on windows
decouple audio-mixer packet receipt from main thread
attempt to change buffers to 1MB only
require presence of LibOVR for relative position from OculusManager
Merge pull request #3287 from birarda/oculus-dk2

require presence of LibOVR for relative position from OculusManager
Merge pull request #3286 from birarda/mixer-analytics

de-couple audio mixer packet receive thread from processing
Merge pull request #3284 from wangyix/master

Made JitterTester work on Windows
Merge branch 'master' into 19616