Add "Releases" anchor to navigate to Releases.

https://sourceforge.net/p/scintilla/feature-requests/1543/

doc/LexillaHistory.html

@@ -37,6 +37,7 @@ <h1>History of Lexilla</h1>
        Lexilla was originally code that was part of the Scintilla project.
        Thus it shares much of the history and contributors of Scintilla before it was extracted as its own project.
     </p>
+    <a href="#Releases">Releases</a>
     <h2>Contributors</h2>
     <p>
        Thanks to all the people that have contributed patches, bug reports and suggestions.
@@ -591,7 +592,7 @@ <h2>Contributors</h2>
 	<td>HoTschir</td>
     </tr>
     </table>
-    <h2>Releases</h2>
+    <h2 id="Releases">Releases</h2>
     <h3>
        <a href="https://www.scintilla.org/lexilla543.zip">Release 5.4.3</a>
     </h3>