Default osvr_server_config.json with client-side prediction

[DuFF14]

After the client-side prediction merge (https://github.com/OSVR/OSVR-Core/pull/399), the default config file that ships with OSVR runtime installation and snapshot seems to be sub-optimal. When I turn my head and stop, tracking overshoots a bit in the direction of the turn, then snaps back into place.

If I remove the part of the config file that relates to positional tracking, performance is better. The behavior I've described happens without the camera connected. I've yet to test with client-side prediction and positional tracking config with the camera connected.

[demonixis]

I got the same issue with the tracker connected.