Update to the purge alert mail

I have added some text and links to the purge mail.

issue#161

ui/nG6/lib/class.tx_nG6_utils.php

@@ -231,6 +231,10 @@ class tx_nG6_utils {
 		}else{
 			$template_mail .= '<p>###EMAILS###</p>';
 		}
+		
+$template_mail.='The nG6 purge process is undergoing an important overhaul.</br>
+You can visit our FAQ at the following address : https://ng6.toulouse.inra.fr/index.php?id=57 .</br>
+If you have any question or demand, do not hesitate to contact our support team at ng6-support@inrae.fr.</br>';
 
 $template_mail.='<p>Yours sincerely</p>
 <p>nG6 team (for GeT-Genotoul and Bioinfo-Genotoul facilities)</p>