Non-affine matrix issue reported by Len Trigg

doc/TODO.txt

@@ -8,6 +8,7 @@ o It's now possible to start a new rendering while one is already running (which
   -> turn off most (or all) interaction while rendering
   -> Lock all or only one MainWindow (MDI)?
 o Look into the polygon winding and rotate_extrude() problem reported by Britton
+o CGAL Aff_transformation_3 doesn't support non-affine transformations (non-aff-matrix.scad)
 
 STL Import BUGS
 ---------------

testdata/scad/non-aff-matrix.scad

@@ -0,0 +1,6 @@
+multmatrix(m = [[1, 0,  0,      0],
+                [0, 1,  0,      0],
+                [0, 0,  1,      0],
+                [0, 0,  -0.02, 1]]) 
+ linear_extrude(height=20) circle(r=10);
+