updated docs for release

Author: ttl-octave

docs/index.html

@@ -61,7 +61,7 @@
             </div>
             <div class="col-sm-9 col-md-10">
               <h3 class="d-inline-block mr-2">control</h3>
-              <b>3.99.99+&nbsp;2024-xx-xx</b>
+              <b>4.0.0&nbsp;2024-01-04</b>
               <p class="indent">
                 Control package for GNU Octave including system analysis and  control synthesis. The package uses routines of the SLICOT-Reference library.
               </p>