update README.md

Author: haoAddsearch

README.md

@@ -343,8 +343,8 @@ Set stats session ID if user token is generated by your site.
 client.setStatsSessionId(userToken);
 ```
 
-If session ID is not set, a UUID is generated and stored in AddSearch's cookie. Cookie's name: addsearchUserToken
-Specify how many dates user token stay in cookie. Default is 180 dates.
+If session is not set, a UUID is generated and stored in a cookie named 'addsearchUserToken`.
+Specify the expiration date of the cookie. Default is 180.
 ```js
 // Defaults - isEnabled: false, expirationDates: 180
 client.enablePersonalizationTracking(isEnabled, expirationDates);