Add note to remind sysadmin to encourage end users to report spams by moving spams to Junk folder.

en_US/iredmail-easy/iredmail-easy.release.notes.md

@@ -19,6 +19,8 @@
 
     The spam/ham learning will be performed every 10 minutes with a cron job.
 
+    __Now encourage your users to report spams by moving spams to `Junk` folder. :)__
+
 * Fixed issues:
     - Can not login to XMPP service (Prosody) due to incorrect permission of
       auth module files.

html/iredmail-easy.release.notes.html

@@ -42,6 +42,7 @@
 learning later, vice verse, message moved out of Junk will be copied
 for ham learning later.</p>
 <p>The spam/ham learning will be performed every 10 minutes with a cron job.</p>
+<p><strong>Now encourage your users to report spams by moving spams to <code>Junk</code> folder. :)</strong></p>
 </li>
 <li>
 <p>Fixed issues:</p>