Add C++14 support based on https://github.com/boostorg/config/pull/39

test/boost_no_cxx14_generic_lambda.ipp

@@ -0,0 +1,23 @@
+
+//  (C) Copyright Kohei Takahashi 2014
+
+//  Use, modification and distribution are subject to the
+//  Boost Software License, Version 1.0. (See accompanying file
+//  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/libs/config for more information.
+
+//  MACRO:         BOOST_NO_CXX14_GENERIC_LAMBDAS
+//  TITLE:         C++14 generic lambda unavailable
+//  DESCRIPTION:   The compiler does not support C++14 generic lambda
+
+namespace boost_no_cxx14_generic_lambdas
+{
+
+int test()
+{
+    return [](auto ret) { return ret; } (0);
+}
+
+}
+