[base] Use prop 'values' instead of 'value'

Author: mpsonntag

odml/base.py

@@ -357,8 +357,8 @@ def itervalues(self, max_depth=None, filter_func=lambda x: True):
         :type filter_func: function
         """
         for prop in [p for p in self.iterproperties(max_depth=max_depth)]:
-            if filter_func(prop.value):
-                yield prop.value
+            if filter_func(prop.values):
+                yield prop.values
 
     def contains(self, obj):
         """