Merge pull request #186 from intellimath/master

Add unicode slicing support
clean up in unicode slicing utility function, fix 'self' reference in PyUnicode_READY() call
fix typo
fix copy+paste bug
changelog
move dict.*() method implementations from Optimize.c to Builtin.c
automatically convert dict.iter*() and dict.view*() methods to .keys/values/items() in Py3 for typed dicts
remove test that no longer compiles after C-ifying dict.iterkeys()
fix test in Py3.1