add missing documentation (#244)

Author: uschindler

src/main/docs/bundled-signatures.html

@@ -53,7 +53,7 @@ <h1>Bundled Signatures Documentation</h1>
 
 <li><strong><tt>commons-io-unsafe-*</tt>:</strong> If your application uses the famous <i>Apache Common-IO</i> library,
 this adds signatures of all methods that depend on default charset
-(for versions <tt>*</tt> = 1.0, 1.1, 1.2, 1.3, 1.4, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8.0, 2.9.0, 2.10.0, 2.11.0, 2.12.0, 2.13.0, 2.14.0).</li>
+(for versions <tt>*</tt> = 1.0, 1.1, 1.2, 1.3, 1.4, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8.0, 2.9.0, 2.10.0, 2.11.0, 2.12.0, 2.13.0, 2.14.0, 2.15.0, 2.15.1).</li>
 
 </ul>