FIX: identify properties via name

src/caosadvancedtools/cfood.py

@@ -78,9 +78,13 @@ class AbstractCFood(object):
     # move to api?
     def set_property(entity, prop, value):
         # TODO only do something when it is necessary?
+        if isinstance(prop, db.Entity):
+            name = prop.name
+        else:
+            name = prop
 
-        while entity.get_property(prop) is not None:
-            entity.remove_property(prop)
+        while entity.get_property(name) is not None:
+            entity.remove_property(name)
         entity.add_property(prop, value)
 
     @staticmethod