Small fixes.

nifty/plotting/plottable.py

 from abc import ABCMeta, abstractmethod
 
 
-class Plottable:
+class Plottable(object):
     __metaclass__ = ABCMeta
 
     @abstractmethod

nifty/spaces/space/space.py

@@ -151,6 +151,7 @@ from keepers import Loggable,\
 
 from nifty.plotting import Plottable
 
+
 class Space(Versionable, Loggable, Plottable, object):
     """
         ..                            __             __