reporter returns walk_result

Author: danielaparker

doc/ref/jsonschema/json_schema/validate.md

@@ -42,8 +42,10 @@ to a [json_visitor](../../corelib/basic_json_visitor.md).
     <td>reporter</td>
     <td>A function object with signature equivalent to 
     <pre>
-           void fun(const validation_message& msg)</pre>
-which accepts an argument of type <a href="../validation_message.md">validation_message</a>.</td> 
+           walk_result fun(const validation_message& msg)</pre>
+which accepts an argument of type <a href="../validation_message.md">validation_message</a> and
+returns a <a href="../walk_result.md">walk_result</a>.
+</td> 
   </tr>
   <tr>
     <td>patch</td>