adding openmoc material support

[shimwell]

Adding openmoc support should be possible using inbuild openmc methods, perhaps this helps

        try:
            import openmoc
        except ImportError as err:
            raise err('openmoc not found, Material.openmoc_material method not available')

        self.openmoc_material = openmc.openmoc_compatible.get_openmoc_material

[shimwell]

The pip install openmoc needs swig, unfortunatly the pip install for swig pip install swiglpk does not appear to be quite enough to get openmoc compiled during the install. Users will have to do apt-get install swig prior to install ing openmoc with pip and using openmoc