C-grids conversion to SU2 native format

[Mauro Minervino]

Hi everyone, for those interested, here you can find a couple of simple C++ codes to convert C-type meshes generated by Construct2D into the native grid format used by Stanford University Unstructured flow solver (.su2) and to generate coarser meshes (for grid sensitivity studies) from a reference fine PLOT3D:
https://github.com/m-minervino/P2D2SU2