Create a development branch for the hash library.

svn path=/branches/hash/boost/pending/is_heap.hpp; revision=38869
Merge from trunk.

svn path=/branches/hash/boost/graph/; revision=39016
Merge from trunk.

svn path=/branches/hash/boost/graph/; revision=39287
Merge with the offending files removed.

svn path=/branches/hash/boost/graph/; revision=39995
Merge from trunk.

svn path=/branches/hash/libs/graph/; revision=40260