add vcglib

vcglib/apps/meshes/Tetraascii.ply

@@ -0,0 +1,18 @@
+ply
+format ascii 1.0
+comment VCGLIB generated
+element vertex 4
+property float x
+property float y
+property float z
+element face 4
+property list uchar int vertex_indices
+end_header
+1 1 1 
+-1 1 -1 
+-1 -1 1 
+1 -1 -1 
+3 0 1 2 
+3 0 2 3 
+3 0 3 1 
+3 3 2 1