Tweaks and bugfixes for the asset variant system and some other things. Should fix some of the last texture stragglers that wouldn't load and some of the stuttering when compressing locally.

New Features:

- Added RenderQueue property to FontMaterial (requested by @Coffee )
- Added "Leap Tracking Enabled" setting that allows to enable/disable Leap motion (requested by @Danyy59)

Optimizations:

- Reduced multithreading level for local block texture compression, to avoid stuttering and CPU overload (based on reports by @DeliriousJax and sample model file provided by @Smol🍪 )
- Local asset variant generation will now use a queue, rather than spamming multiple threads, further contributing to the CPU overload and stuttering
- Session and world switcher orbs will use RGBA32 textures rather than block compressed variants to avoid repetitious local compressions of those textures as the thumbnails are updated

Tweaks:

- 3D Model and image importers will no longer include filename extension in the imported object name (based on feedback by @Karel )

Bugfixes:

- Fixed issue where the asset variant system would fallback to a different version of the asset half-way through the loading process, resulting in corrupt textures (based on reports by @Shifty and @Coffee )
- Fixed issue with certain textures being incorrectly classified, causing them to not load and generate variants correctly
-- This should fix last few straggles that wouldn't load (reported/encountered by @Shifty, @Coffee, @InsaneGrox and @Veer).
-- If your textures don't load, try giving it a few hours and restart Neos in between. If they still don't load then report the issue with the texture URL
- Fixed creating Inventory links from existing links not working correctly (reported by @ProbablePrime and others)
- Fixed incorrect Oculus Touch controller offset fro NeosAvatarControllerSpawner (reported by @Bom "Bitman" bomb (PolyLogiX) )
- Fixed broken "message" command for Headless client (reported by @Bom "Bitman" bomb (PolyLogiX))
- Tweaked Material Gun undo step creation to help fix cases where undo steps randomly break (reported by @GearBell and others, let me know if you still notice this happening)