Add a trivial test to see if the deprecated hash headers compile okay when included.

[SVN r39994]

test/hash_deprecated_headers.cpp

@@ -0,0 +1,26 @@
+
+// Copyright 2007 Daniel James.
+// Distributed under 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)
+
+// All these headers are meant output a warning, but not cause the compilation
+// to fail.
+
+#include <boost/functional/hash/deque.hpp>
+#include <boost/functional/hash/list.hpp>
+#include <boost/functional/hash/map.hpp>
+#include <boost/functional/hash/pair.hpp>
+#include <boost/functional/hash/set.hpp>
+#include <boost/functional/hash/vector.hpp>
+
+// And a quick check that the hash library was included.
+// Strictly speaking I should do this once for each header
+// but that would just be wasting the testing resources.
+
+#include <vector>
+
+int main() {
+    std::vector<int> v;
+    boost::hash<std::vector<int> > x;
+    x(v);
+}