added the test file

Author: SergioRAgostinho

test/ply_benchmark.ply

@@ -0,0 +1,19 @@
+ply
+format ascii 1.0
+element vertex 4
+property float x
+property float y
+property float z
+property uchar red
+property uchar green
+property uchar blue
+property uchar alpha
+element face 2
+property list uchar int vertex_indices
+end_header
+4.23607 0 1.61803 255 0 0 255
+2.61803 2.61803 2.61803 0 255 0 0
+0 1.61803 4.23607 0 0 255 128
+0 -1.61803 4.23607 255 255 255 128
+3 0 1 2
+3 1 2 3