updated move assignments and swap operations to "N4258: Cleaning-up noexcept in the Library, Rev 3" with some customizations.

include/boost/container/list.hpp

@@ -339,7 +339,8 @@ class list
    //!   propagate_on_container_move_assignment is true or
    //!   this->get>allocator() == x.get_allocator(). Linear otherwise.
    list& operator=(BOOST_RV_REF(list) x)
-      BOOST_CONTAINER_NOEXCEPT_IF(allocator_traits_type::propagate_on_container_move_assignment::value)
+      BOOST_CONTAINER_NOEXCEPT_IF(allocator_traits_type::propagate_on_container_move_assignment::value
+                                  || allocator_traits_type::is_always_equal::value)
    {
       BOOST_ASSERT(this != &x);
       NodeAlloc &this_alloc = this->node_alloc();
@@ -931,6 +932,8 @@ class list
    //!
    //! <b>Complexity</b>: Constant.
    void swap(list& x)
+      BOOST_CONTAINER_NOEXCEPT_IF(allocator_traits_type::propagate_on_container_swap::value
+                               || allocator_traits_type::is_always_equal::value)
    {  AllocHolder::swap(x);   }
 
    //! <b>Effects</b>: Erases all the elements of the list.