Crash caused by DD stepping and AutoTune both hacking the RenderFarClip. Added a proxy tunables structure to allow the main thread to tweak the tunables while the work is still done on the perf thread.
Also adds the ability to see the "revised" render time rather than the original. This can be confusing when auto tuning so defaults off.
Cleaned up some text
* enables autotune setting panel
* adds help_topic fs_performance_floater (placeholder page created)
* adds new optional control of maxnonimpostors based on distance from camera.
- cleanup and ratioanlise code altering the settings.
- rename to make units more obvious
- make slider logarithmic to make the req'd range more practical.
make the auto-tuning more robust and a little less trigger happy.
- fix incorrect logic that blocked maxnonimposter control from working
- Zoom to Avatar instead of cam to avatar for consistency rather than correctness.
-open phototools not phototools_camera.
Ansariel