Merge pull request OAI#1182 from krishahn/callback-object-example

edit Callback Object Example

Author: Ron

versions/3.0.md

@@ -1778,7 +1778,7 @@ $response.header.Location | http://example.org/subscription/1
 
 ##### Callback Object Example
 
-A callback to the URL specified by the `url` parameter in the request
+The following example shows a callback to the URL specified by the `url` parameter in the request:
 
 
 ```yaml