Update comment + six.text_type instead of str for name

Change-Id: I84c683f3ef0c2c2369d845c234e94e532346d909

taskflow/atom.py

@@ -139,6 +139,7 @@ class Atom(object):
 
     @property
     def name(self):
+        """A non-unique name for this atom (human readable)."""
         return self._name
 
     def __str__(self):

taskflow/flow.py

@@ -48,7 +48,7 @@ class Flow(object):
     """
 
     def __init__(self, name):
-        self._name = str(name)
+        self._name = six.text_type(name)
 
     @property
     def name(self):