Converted parametric functions test from Tcl to Python

Restored testing of the parametric functions in computational geometry.

Change-Id: Idd9979b07ec539bc14865259f2db2368558d9f2d

Common/ComputationalGeometry/Testing/Python/CMakeLists.txt

+if(VTK_PYTHON_EXE)
+  set(tests)
+  if(VTK_DATA_ROOT)
+    # Tests written in Python that require VTKData
+    # These tests should use vtk.test.Testing.
+    set(tests
+      ${tests}
+      TestParametricFunctions
+    )
+  else()
+    # Tests written in Python that do NOT require VTKData
+    # These tests should use vtk.test.Testing.
+    set(tests
+      ${tests}
+    )
+  endif()
+  if(tests)
+    foreach(tfile ${tests})
+      add_test(NAME ${vtk-module}Python-${tfile}
+        COMMAND ${VTK_PYTHON_EXE}
+          ${CMAKE_CURRENT_SOURCE_DIR}/${tfile}.py
+          -D ${VTK_DATA_ROOT}
+          -B ${VTK_DATA_ROOT}/Baseline/Graphics)
+    endforeach()
+  endif()
+else()
+  message(FATAL_ERROR "No Python tests added!")
+endif()