Merge latest changes for unordered. Improved compatability and a few tweaks.

Merged revisions 53127,53253,53256,53311,53314,53316-53318 via svnmerge from 
https://svn.boost.org/svn/boost/trunk

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  r53127 | danieljames | 2009-05-20 07:43:38 +0100 (Wed, 20 May 2009) | 1 line
  
  Better configuration for boost.unordered.
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  r53253 | danieljames | 2009-05-25 20:14:07 +0100 (Mon, 25 May 2009) | 3 lines
  
  Add explicit destructors to the unordered containers. Refs #2908.
  
  Isn't really needed but it doesn't hurt.
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  r53256 | danieljames | 2009-05-25 20:45:23 +0100 (Mon, 25 May 2009) | 1 line
  
  Unordered change log for explicit destructors.
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  r53311 | danieljames | 2009-05-27 18:42:01 +0100 (Wed, 27 May 2009) | 1 line
  
  Missing changelog entry.
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  r53314 | danieljames | 2009-05-27 18:44:09 +0100 (Wed, 27 May 2009) | 1 line
  
  Use lightweight_test for unordered.
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  r53316 | danieljames | 2009-05-27 19:19:32 +0100 (Wed, 27 May 2009) | 1 line
  
  Some workarounds for old versions of Borland.
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  r53317 | danieljames | 2009-05-27 19:32:22 +0100 (Wed, 27 May 2009) | 1 line
  
  Fix a change accidentally included in the last commit.
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  r53318 | danieljames | 2009-05-27 19:32:38 +0100 (Wed, 27 May 2009) | 1 line
  
  Remove an unused function.
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[SVN r53465]

test/unordered/at_tests.cpp

@@ -16,8 +16,8 @@ UNORDERED_AUTO_TEST(at_tests) {
     x["one"] = 1;
     x["two"] = 2;
 
-    BOOST_CHECK(x.at("one") == 1);
-    BOOST_CHECK(x.at("two") == 2);
+    BOOST_TEST(x.at("one") == 1);
+    BOOST_TEST(x.at("two") == 2);
 
     try {
         x.at("three");