Natsura 0.5.11.0

Improved rigging and wind tools for Unreal Nanite Assemblies.

• Added experimental wind tools for Unreal (Wind Init, Wind Config, Unreal Wind)
• Updated Nanite Assembly Exporter with multi-trunk rig support
• More robust rigging of clusters (fixes Unreal import bug from missing skinning info)
• Rig and Skin simplification with new "simplification" slider using refine
• Updated rig and skin method to support multi-trunks
• Delete joints now correctly fixes up parentid to ensure valid rigs
• Cluster Decorator primitive attributes transferred using more robust method
• Fixed small panel bugs