netbeans requires nb-javac for tomcat

developers.html

@@ -2420,6 +2420,9 @@ netbeans_jdkhome="C:\Program Files\Java\jdk1.8.0_221"</pre>
           <li>
               Ensure that <code>CATALINA_HOME</code> points to root directory of current Tomcat installation.
           </li>
+          <li>
+              Ensure that <code>nb-javac</code> plugin is installed.
+          </li>
           <li>
               <span style="color:darkorange"><b>Warning, troubleshooting in progress:</b></span>
               not working in Netbeans&nbsp;12.3, unsuccessful backtracking to Netbeans&nbsp;12.2 and OpenJDK&nbsp;14.02, 
@@ -3024,7 +3027,7 @@ which can lead to the Internet of Things becoming the Web of Things. </i>
             <a href="https://savage.nps.edu/developers.html">https://savage.nps.edu/developers.html</a>
         </blockquote>
         <blockquote>
-            Revised 14 May 2021.
+            Revised 18 May 2021.
         </blockquote>
 
         <p>