Create a branch for documentation work.

svn path=/branches/doc/boost/functional/hash.hpp; revision=44584
Group functions in the hash header - requires Frank's free-function-group fix.

svn path=/branches/doc/libs/functional/hash/; revision=45282
Use root links in quickbook.

svn path=/branches/doc/libs/functional/hash/; revision=45364
Add boost.root to standalone hash documentation.

svn path=/branches/doc/libs/functional/hash/; revision=45365
Merge latest changes from unordered.

svn path=/branches/doc/libs/functional/hash/; revision=45892