Add extra title page

This makes it compatible with `--direct_html`.

Author: nik9000

book-extra-title-page.html

@@ -0,0 +1,62 @@
+ <div class="authorgroup">
+  <div class="author">
+   <h3 class="author">
+    <span class="firstname">
+     Clinton
+    </span>
+    <span class="surname">
+     Gormley
+    </span>
+   </h3>
+  </div>
+  <div class="author">
+   <h3 class="author">
+    <span class="firstname">
+     Zachary
+    </span>
+    <span class="surname">
+     Tong
+    </span>
+   </h3>
+  </div>
+ </div>
+</div>
+<div>
+ <p class="copyright">
+  Copyright © 2014, 2015 Elasticsearch
+ </p>
+</div>
+<div>
+ <div class="legalnotice">
+  <a id="id-1.1.3">
+  </a>
+  <p>
+   This work is licensed under a
+   <a class="ulink" href="http://creativecommons.org/licenses/by-nc-nd/3.0/" target="_top">
+    Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License
+   </a>
+   .
+  </p>
+ </div>
+</div>
+<div>
+ <div class="abstract">
+  <p class="title">
+   <strong>
+    Abstract
+   </strong>
+  </p>
+  <p>
+   If you would like to purchase an eBook or printed version of this book once it is complete, you can do so from O'Reilly Media:
+   <a class="ulink" href="http://www.oreilly.com/catalog/0636920028505" target="_top">
+    Buy this book from O'Reilly Media
+   </a>
+  </p>
+  <p>
+   We welcome feedback – if you spot any errors or would like to suggest improvements, please
+   <a class="ulink" href="https://github.com/elasticsearch/elasticsearch-definitive-guide/issues" target="_top">
+    open an issue
+   </a>
+   on the GitHub repo.
+  </p>
+ </div>