Currently, only support "Normal" and "Inversion" modes, "Normal" means normal mesh union, "Inversion" means mesh diff, it behaves like subtract itself from the previous mesh.
Many source file name and data type are prefixed by "skeleton" before, now all are refactored.
The class MeshResultContext represents the outcome of mesh generation before, now we have material, pose and animation, so we just rename it as Outcome.
huxingyi