Make boost::tuple tuple-like to support structured bindings

test/Jamfile

@@ -5,4 +5,7 @@ test-suite tuple :
     [ run tuple_test_bench.cpp ]
     [ run io_test.cpp ]
     [ run another_tuple_test_bench.cpp ]
+    [ run std_tuple_size.cpp ]
+    [ run std_tuple_element.cpp ]
+    [ run structured_bindings.cpp ]
     ;