modify BaseTraitedSpec for tab completion

Author: leej3

nipype/interfaces/base/specs.py

@@ -72,6 +72,7 @@ def __init__(self, **kwargs):
         self.trait_set(trait_change_notify=False, **undefined_traits)
         self._generate_handlers()
         self.trait_set(**kwargs)
+        self.__all__ = self.class_editable_traits()
 
     def items(self):
         """ Name, trait generator for user modifiable traits
@@ -351,6 +352,7 @@ def __deepcopy__(self, memo):
         # clone twice
         dup = self.clone_traits(memo=memo)
         dup.trait_set(**dup_dict)
+        self.__all__ = super(BaseTraitedSpec,self).__all__
         return dup