Make the slider work

Still WIP though: need to make vector work with the 'contains display name' rule being an override

src/notifications/VectorPushRulesDefinitions.js

@@ -65,7 +65,7 @@ module.exports = {
     // Messages containing user's display name
     // (skip contains_user_name which is too geeky)
     ".m.rule.contains_display_name": new VectorPushRuleDefinition({
-        kind: "underride",
+        kind: "override",
         description: "Messages containing my name",
         vectorStateToActions: { // The actions for each vector state, or null to disable the rule.
             on: StandardActions.ACTION_NOTIFY,