meshIO now has a framework to set the curvature of an input mesh. This is still an early and incomplete implimentation. This has also changed the call signature a bit for GetMesh as that now returns a reference to the mesh (which is fully owned by the meshIO object)
BREAKING CHANGE: all calls to meshIO::GetMesh now must expect a mfem::Mesh&
a higher resolution mesh is useful in the core of a polytrope, I updated the mesh generation script to make the center of the star much higher resolution
