For anyone who might be interested, I recently updated and uploaded a Linux version of MeoMotion (previously only Windows). It allows bone-based sprite animations including distortions for things like hair or clothing. It now also has a built-in sprite-packer option. The runtimes are free for commercial use and you are free to modify them in any way you need.
The main target is MonoGame / XNA but there are runtime examples for DirectX(C++), OpenGL(C++), SharpDX(C#), and SDL2(pure).
If you're interested it can be found on my site under MeoMotion:
http://www.alienscribbleinteractive.com/MeoMotion.html