Blender ksanim/knh exporter 0.4

Compatibility with Blender 2.80 and 2.81, same functionality as before otherwise.

The main issue I know of is you can't use it on root level nodes, only objects with parents.

For exporting driver animations using the driver file I created @ https://www.assettocorsa.net/forum/index.php?threads/bone-animation-rig-blender.34594/ - or just general-purpose ksanim exporting when you don't want to do it by exporting an animated fbx.