* add LOD switching for clutter model instances
* DrawModelInstamce with correct LOD level
* removed some useless comments. move stuff around
https://files.facepunch.com/antopilo/1b0711b1/sbox-dev_AcVXDWDDah.mp4
* use biggest scale axis to determine screen coverage for clutter lod level
* clamp LOD in managed
* clamp lod in native
* rename lod Count to maxLodCount