Add a test that unnecessary copies aren't made of objects inserted.

Make the exception tests track the allocator usage.
Speed up the exception tests a bit.


[SVN r3490]

test/unordered/Jamfile.v2

@@ -18,6 +18,7 @@ test-suite unordered-tests
         [ run copy_tests.cpp ]
         [ run assign_tests.cpp ]
         [ run insert_tests.cpp ]
+        [ run unnecessary_copy_tests.cpp ]
         [ run erase_tests.cpp ]
         [ run erase_equiv_tests.cpp ]
         [ run find_tests.cpp ]