off-simple-0.1: tests/samples/cube.off

OFF
8 6 12
 1.0   1.0   1.0
-1.0   1.0   1.0
-1.0  -1.0   1.0
 1.0  -1.0   1.0
 1.0   1.0  -1.0
-1.0   1.0  -1.0
-1.0  -1.0  -1.0
 1.0  -1.0  -1.0
4  0 1 2 3
4  7 6 5 4
4  0 3 7 4
4  3 2 6 7
4  2 1 5 6
4  0 4 5 1