move.h (__is_nothrow_swappable): Add.

2011-06-22  Daniel Krugler  <daniel.kruegler@googlemail.com>
	    Paolo Carlini  <paolo.carlini@oracle.com>

	* include/bits/move.h (__is_nothrow_swappable): Add.
	(swap(_Tp(&)[_Nm], _Tp(&)[_Nm])): Use noexcept.
	* include/bits/algorithmfwd.h: Adjust.
	* testsuite/25_algorithms/swap/noexcept.cc: New.


Co-Authored-By: Paolo Carlini <paolo.carlini@oracle.com>

From-SVN: r175277