Factored out BOOST_CONCEPT_ASSERT into concept_check/assert.hpp

Fixed the implementation for GCC 3.3.x and comeau
Added BOOST_CONCEPT_WHERE, and tests


[SVN r33887]

where.cpp

@@ -0,0 +1,13 @@
+// Copyright David Abrahams 2006. 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)
+#include <vector>
+#undef NDEBUG
+#include "fake_sort.hpp"
+
+int main()
+{
+  std::vector<int> v;
+  fake_sort(v.begin(), v.end());
+  return 0;
+}