MeshLab OBJ mesh import

[afarnudi]

We need support for OBJ mesh import.

OBJ is a text file that contains the vertex coordinates followed by the face (triangle) vertex relations.
This file will be well suited for the Membrane class.

The main issue would be that a single obj file can contain many triangulated meshes.
We can add a feature that identifies a single mesh in the OBJ file and imports it.

As another feature, one can also propose a batch import option that imports all membranes in an OBJ file

[afarnudi]

The label is not the same as what appears in the obj file.