Implemented C++20's uninitialized_construct_using_allocator and make_obj_using_allocator.

Author: igaztanaga

doc/container.qbk

@@ -1438,7 +1438,8 @@ use [*Boost.Container]? There are several reasons for that:
 
 * Implemented heterogeneous overloads from C++23 ([@http://wg21.link/p2077r3 P2077]) and C++26 ([@http://wg21.link/P2363 P2363]).
 * In C++20 compilers, `static_vector<T>`'s destructor is now trivial if `T` is trivial.
-* Implemented C++20's [classref boost::container::uninitialized_construct_using_allocator uninitialized_construct_using_allocator].
+* Implemented C++20's [funcref boost::container::uninitialized_construct_using_allocator uninitialized_construct_using_allocator]
+  and [funcref boost::container::make_obj_using_allocator make_obj_using_allocator].
 * Fixed bugs/issues:
    * [@https://github.com/boostorg/container/issues/323 GitHub #323: ['"flat_tree::try_emplace UB"]].