libstdc++: Fix and improve std::vector<bool> implementation.

libstdc++: Fix and improve std::vector<bool> implementation.

Do not consider allocator noexcept qualification for vector<bool> move
constructor.
Improve swap performance using TBAA like in main vector implementation. Bypass
_M_initialize_dispatch/_M_assign_dispatch in post-c++11 modes.

libstdc++-v3/ChangeLog:

	* include/bits/stl_bvector.h
	[_GLIBCXX_INLINE_VERSION](_Bvector_impl_data::_M_start): Define as
	_Bit_type*.
	(_Bvector_impl_data(const _Bvector_impl_data&)): Default.
	(_Bvector_impl_data(_Bvector_impl_data&&)): Delegate to latter.
	(_Bvector_impl_data::operator=(const _Bvector_impl_data&)): Default.
	(_Bvector_impl_data::_M_move_data(_Bvector_impl_data&&)): Use latter.
	(_Bvector_impl_data::_M_reset()): Likewise.
	(_Bvector_impl_data::_M_swap_data): New.
	(_Bvector_impl::_Bvector_impl(_Bvector_impl&&)): Implement explicitely.
	(_Bvector_impl::_Bvector_impl(_Bit_alloc_type&&, _Bvector_impl&&)): New.
	(_Bvector_base::_Bvector_base(_Bvector_base&&, const allocator_type&)):
	New, use latter.
	(vector::vector(vector&&, const allocator_type&, true_type)): New, use
	latter.
	(vector::vector(vector&&, const allocator_type&, false_type)): New.
	(vector::vector(vector&&, const allocator_type&)): Use latters.
	(vector::vector(const vector&, const allocator_type&)): Adapt.
	[__cplusplus >= 201103](vector::vector(_InputIt, _InputIt,
	const allocator_type&)): Use _M_initialize_range.
	(vector::operator[](size_type)): Use iterator operator[].
	(vector::operator[](size_type) const): Use const_iterator operator[].
	(vector::swap(vector&)): Add assertions on allocators. Use _M_swap_data.
	[__cplusplus >= 201103](vector::insert(const_iterator, _InputIt,
	_InputIt)): Use _M_insert_range.
	(vector::_M_initialize(size_type)): Adapt.
	[__cplusplus >= 201103](vector::_M_initialize_dispatch): Remove.
	[__cplusplus >= 201103](vector::_M_insert_dispatch): Remove.
	* python/libstdcxx/v6/printers.py (StdVectorPrinter._iterator): Stop
	using start _M_offset.
	(StdVectorPrinter.to_string): Likewise.
	* testsuite/23_containers/vector/bool/allocator/swap.cc: Adapt.
	* testsuite/23_containers/vector/bool/cons/noexcept_move_construct.cc:
	Add check.