Application#stop(boolean): fix javadoc args issue (#2038)

* Application#stop(boolean): fix javadoc args conditions issue

* Application#stop(boolean): fix args javadoc

jme3-core/src/main/java/com/jme3/app/Application.java

@@ -226,7 +226,7 @@ public interface Application {
      * After the application has stopped, it cannot be used anymore.
      * 
      @param waitFor true→wait for the context to be fully destroyed,
-     * true→don't wait
+     * false→don't wait
      */
     public void stop(boolean waitFor);
 

jme3-core/src/main/java/com/jme3/app/LegacyApplication.java

@@ -618,7 +618,7 @@ public class LegacyApplication implements Application, SystemListener {
      * After the application has stopped, it cannot be used anymore.
      *
      * @param waitFor true→wait for the context to be fully destroyed,
-     * true→don't wait
+     * false→don't wait
      */
     @Override
     public void stop(boolean waitFor) {