add the IK solver with IKchain handler
minor change & comment in the IK solver
add a simple ik demo
update the README
add description for ik_demo
clean the skinning shader
Fixed normal buffer size from nvertices to npoints
clean skinning shader
add dual quaternion & matrix3x4 typedef
update glm version
minor cmake change
implemented Dual Quaternion Blend Skinning; Improved skinning matrices storage for memory bandwith; aggregate skinning stages