Remove null limitation

Author: MGatner

README.md

@@ -104,17 +104,8 @@ setting()->forget('App.siteName');
 
 The following are known limitations of the library:
 
-1. Using the `setting()` helper method does not support setting a `null` value on a property. For most cases, you are 
-better off forgetting the value or setting it to an empty string. If you need to, you can set it by grabbing 
-the service and using the `set()` method:
-
-```php
-service('settings')->set('App.siteName', null);
-setting()->set('App.siteName', null);
-```
-
-2. You can currently only store a single setting at a time. While the `DatabaseHandler` uses a local cache to
+1. You can currently only store a single setting at a time. While the `DatabaseHandler` uses a local cache to
 keep performance as high as possible for reads, writes must be done one at a time. 
-3. You can only access the first level within a property directly. In most config classes this is a non-issue, 
+2. You can only access the first level within a property directly. In most config classes this is a non-issue, 
 since the properties are simple values. Some config files, like the `database` file, contain properties that
 are arrays.