Merge #2326

2326: Add `pref` field to prefCompare filter object r=tiftran a=mythmon



Co-authored-by: Michael Cooper <mythmon@gmail.com>

normandy/recipes/filters.py

@@ -323,6 +323,12 @@ class PrefCompareFilter(BaseFilter):
 
         ``preferenceValue``
 
+    .. attribute:: pref
+
+        The preference to change.
+
+        :example: ``fission.experiment.max-origins.qualified``
+
     .. attribute:: value
 
         string, boolean, or number.