replace models since Milkshape 1.8.5 uses subversion 3 for vertex_extra which is unkown...
preparation for skeletal animation in graphics contexts
milkshape3d version 1.8.5 saves subversion 3
vertex shader for skeletal animation
structure for skeletal animation
allow structure in model
load animation data in modelloader from file
show first try of skeletal animation (sucks atm...) :D