add set property action in background

src/background/actions/index.js

@@ -1,4 +1,5 @@
 export default {
   // Settings
   SETTING_SET_SETTINGS: 'setting.set.settings',
+  SETTING_SET_PROPERTY: 'setting.set.property',
 };

src/background/actions/setting.js

@@ -10,4 +10,12 @@ const load = () => {
   });
 };
 
-export { load };
+const setProperty = (name, value) => {
+  return {
+    type: actions.SETTING_SET_PROPERTY,
+    name,
+    value,
+  };
+};
+
+export { load, setProperty };