2014-05-31  Ed Smith-Rowland  <3dw4rd@verizon.net>

	Implement SD-6: SG10 Feature Test Recommendations
	* include/bits/basic_string.h: Add __cpp_lib feature test macro.
	* include/bits/stl_algobase.h: Ditto.
	* include/bits/stl_function.h: Ditto.
	* include/bits/unique_ptr.h: Ditto.
	* include/std/array: Ditto.
	* include/std/chrono: Ditto.
	* include/std/complex: Ditto.
	* include/std/iomanip: Ditto.
	* include/std/mutex: Ditto.
	* include/std/shared_mutex: Ditto.
	* include/std/tuple: Ditto.
	* include/std/type_traits: Ditto.
	* include/std/utility: Ditto.
	* testsuite/experimental/feat-cxx14.cc: New.
	* testsuite/experimental/feat-lib-fund.cc: New.