Added appendix b

Author: cassiozen

materials/appendixB.pdf

@@ -77,7 +77,7 @@ <h1>Online Materials</h1>
 <h2><a href="https://github.com/pro-react/">Book Source Code</a></h2>
 <h2>Appendix A: WebPack <small><a href="appendixA.pdf" download>PDF</a> | <a href="appendixA">Web</a></small></h2>
 <h2>Appendix B: JavaScript ES2015 <small>Coming soon</small></h2>
-<h2>Appendix C: Functional JavaScript <small>Coming soon</small></h2>
+<h2>Appendix C: Functional JavaScript <small><a href="appendixB.pdf" download>PDF</a></small></h2>
 </div>
 </section>