Move the hash extensions into their own file. Merged revisions 42735 via svnmerge from https://svn.boost.org/svn/boost/branches/unordered/dev
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r42735 | danieljames | 2008-01-13 19:56:31 +0000 (Sun, 13 Jan 2008) | 1 line
Move the hash extensions into their own file.