Reading Medit Issue

[sloriot]

We have another issue to fix. When I uncomment the calls to writing the mesh in the example mesh_polyhedral_complex_sm.cpp, and feed out.mesh into the example c3t3_example.cpp, and then load after_remeshing.mesh into CGALlab.exe many border facets are missing:

Originally posted by @afabri in #8793 (comment)

[janetournois]

Another issue reading .mesh files
The attached cannot be read. read_MEDIT() seems to succeed but then tds.is_valid() crashes because Euler condition is not satisfied.
Note that the demo can read the vtk version of the same mesh.

99992_tetmesh.zip