add C++ implementation of MACCS keys
(contribution from Roger Sayle)

git-svn-id: svn://svn.code.sf.net/p/rdkit/code/trunk@2411 a5045d30-4826-4484-9c7f-6e55a06ddc77
add MACCS fingerprints to python wrapper

git-svn-id: svn://svn.code.sf.net/p/rdkit/code/trunk@2412 a5045d30-4826-4484-9c7f-6e55a06ddc77