fix: serialized to self._serialized in klepto.archives;
added klepto.crypto a unified interface to hashing, encoding, and pickling;
extended klepto.keymaps to allow hash, encoding, and pickler to be selected;
extended klepto.keymaps to allow chaining of keymaps to make compound keymap;
added test_chaining and test_caching to test the above


git-svn-id: svn+ssh://svn.mystic.cacr.caltech.edu/pathos/klepto@562 8bfda07e-5b16-0410-ab1d-fd04ec2748df
Merge branch 'master' of https://github.com/uqfoundation/klepto