Add date_format example value #97

Author: mpociot

src/Mpociot/ApiDoc/Generators/AbstractGenerator.php

@@ -249,6 +249,7 @@ protected function parseRule($rule, $ruleName, &$attributeData, $seed)
             case 'date_format':
                 $attributeData['type'] = 'date';
                 $attributeData['description'][] = Description::parse($rule)->with($parameters)->getDescription();
+                $attributeData['value'] = date($parameters[0]);
                 break;
             case 'different':
                 $attributeData['description'][] = Description::parse($rule)->with($parameters)->getDescription();