Improve confirmation mails

Change-Id: Ida840dfc4c4477fd8b86a7dcb640360c96c99be1
diff --git a/templates/register.htm b/templates/register.htm
index 60b7bd5..62466fc 100644
--- a/templates/register.htm
+++ b/templates/register.htm
@@ -175,7 +175,7 @@
             </div>
         </div>
         <input pattern="[^\s]{<?php echo $CAPTCHA_LENGTH; ?>,}" required
-            title="Please fill the captcha. It has 5 characters" name="captcha" type="text" id="form3Example6"
+            title="Please fill the captcha. It has <?php echo $CAPTCHA_LENGTH; ?> characters" name="captcha" type="text" id="form3Example6"
             class="form-control" placeholder="Type what you see on the image above" />
             <div class="invalid-feedback">
                 Type what you see on the image above.