fix webmail redirection by redirecting to https://FQDN instead of the

same domain

this is to encourage better security practices by forcing users to use
HTTPS and a canonical URL.

eventually, this is a step towards getting rid of the global /webmail/
alias too.

See #170
See #101
See #1080

.gitattributes

@@ -206,7 +206,6 @@ bureau/admin/stats_members.php -text
 bureau/admin/styles/base.css -text
 bureau/admin/template.php -text
 bureau/admin/web_list.php -text
-bureau/admin/webmail/.htaccess -text
 bureau/admin/webmail/index.php -text
 bureau/class/config.php -text
 bureau/class/config_nochk.php -text

bureau/admin/webmail/index.php

@@ -1,3 +1,4 @@
 <?php
-header ("Location: /webmail/") ;
+include("/var/alternc/bureau/class/local.php");
+header ("Location: https://$L_FQDN/webmail/") ;
 ?>