Update README re: cache (#443)

README.md

@@ -608,27 +608,35 @@ php artisan vendor:publish --provider="Spatie\Permission\PermissionServiceProvid
 
   And update the `models.role` and `models.permission` values
 
-## Troubleshooting
 
-### Cache
+## Cache
 
-If you manipulate permission/role data directly in the database instead of calling the supplied methods, then you will not see the changes reflected in the application, because role and permission data is cached to speed up performance.
+Role and Permission data are cached to speed up performance.
 
-To manually reset the cache for this package, run:
-```bash
-php artisan cache:forget spatie.permission.cache
-```
-
-When you use the supplied methods, such as the following, the cache is automatically reset for you:
+When you use the supplied methods for manipulating roles and permissions, the cache is automatically reset for you:
 
 ```php
-// see earlier in the README for how these methods work:
 $user->assignRole('writer');
 $user->removeRole('writer');
+$user->syncRoles(params);
 $role->givePermissionTo('edit articles');
 $role->revokePermissionTo('edit articles');
+$role->syncPermissions(params);
+```
+
+HOWEVER, if you manipulate permission/role data directly in the database instead of calling the supplied methods, then you will not see the changes reflected in the application unless you manually reset the cache.
+
+### Manual cache reset
+To manually reset the cache for this package, run:
+```bash
+php artisan cache:forget spatie.permission.cache
 ```
 
+### Cache Identifier
+
+TIP: If you are leveraging a caching service such as redis or memcached and there are other sites running on your server, you could run into cache clashes. It is prudent to set your own cache `prefix` in `/config/cache.php` for each application uniquely. This will prevent other applications from accidentally using/changing your cached data.
+
+
 ## Need a UI?
 
 The package doesn't come with any screens out of the box, you should build that yourself. To get started check out [this extensive tutorial](https://scotch.io/tutorials/user-authorization-in-laravel-54-with-spatie-laravel-permission) by [Caleb Oki](http://www.caleboki.com/).