New utility classes, containers, C++14 compatibility, and fixes:

* Add std::equal_to <void> (since C++14)
* Add heterogeneous std::equal (since C++14)
* Add maybe_const
* Add empty_base_optimization
* Add is_constructible specialization for pair, tuple
* Add aged associative containers:
  - aged_set, aged_map, aged_multiset, aged_multimap
  - aged_unordered_set, aged_unordered_map,
  - aged_unordered_multiset, aged_unordered_multimap
* Fix auto keyword pass by reference
* Fix basic_seconds_clock warning and project file

beast/container/aged_set.h

@@ -0,0 +1,42 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of Beast: https://github.com/vinniefalco/Beast
+    Copyright 2013, Vinnie Falco <vinnie.falco@gmail.com>
+
+    Permission to use, copy, modify, and/or distribute this software for any
+    purpose  with  or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#ifndef BEAST_CONTAINER_AGED_SET_H_INCLUDED
+#define BEAST_CONTAINER_AGED_SET_H_INCLUDED
+
+#include "detail/aged_ordered_container.h"
+
+#include <chrono>
+#include <functional>
+#include <memory>
+
+namespace beast {
+
+template <
+    class Key,
+    class Duration = std::chrono::seconds,
+    class Compare = std::less <Key>,
+    class Allocator = std::allocator <Key>
+>
+using aged_set = detail::aged_ordered_container <
+    false, false, Key, void, Duration, Compare, Allocator>;
+
+}
+
+#endif