Add example on writing your own Tag and prepare for TagFactory objects

examples/03-reconstituting-a-docblock.php

@@ -1,4 +1,5 @@
 <?php
+
 require_once(__DIR__ . '/../vendor/autoload.php');
 
 use phpDocumentor\Reflection\DocBlock\Serializer;
@@ -18,6 +19,9 @@ DOCCOMMENT;
 $factory  = DocBlockFactory::createInstance();
 $docblock = $factory->create($docComment);
 
-$serializer              = new Serializer();
+// Create the serializer that will reconstitute the DocBlock back to its original form.
+$serializer = new Serializer();
+
+// Reconstitution is performed by the `getDocComment()` method.
 $reconstitutedDocComment = $serializer->getDocComment($docblock);