New GMPXX_arithmetic_kernel.

Arithmetic_kernel/test/Arithmetic_kernel/GMPXX_arithmetic_kernel.cpp

@@ -0,0 +1,18 @@
+#include <iostream>
+#include <CGAL/basic.h>
+#include <CGAL/GMPXX_arithmetic_kernel.h>
+
+#ifdef CGAL_USE_GMPXX
+
+#include <CGAL/Test/_test_arithmetic_kernel.h>
+
+int main() {
+  std::cout << "TEST GMPXX_arithmetic_kernel" << std::endl;
+  typedef CGAL::GMPXX_arithmetic_kernel AK;
+  CGAL::test_arithmetic_kernel<AK>();
+  return 0;
+}
+
+#else
+int main() { return 0; }
+#endif