short documentation added, path to deliver as configuration option

ADDITIONS/fetchmail.pl

@@ -29,6 +29,12 @@ our $db_password="CHANGE_ME!";
 # Where to create a lockfile; please ensure path exists.
 our $run_dir="/var/run/fetchmail";
 
+# in case you want to use dovecot deliver to put the mail directly into the users mailbox,
+# set "mda" in the fetchmail table to the keyword "dovecot".
+
+# Where the delivery binary is located
+$dovecot_deliver = "/usr/lib/dovecot/deliver";
+
 # instead of changing this script, you can put your settings to /etc/mail/postfixadmin/fetchmail.conf
 # just use perl syntax there to fill the variables listed above (without the "our" keyword). Example:
 # $db_username = 'mail';
@@ -108,7 +114,7 @@ map{
 
 	if ($mda) {
 		if ($mda eq "dovecot") {
-			$cmd.=" mda \"/usr/lib/dovecot/deliver -d ${mailbox}\" ";
+			$cmd.=" mda \"${dovecot_deliver} -d ${mailbox}\" ";
 		} else {
 			$cmd.=" mda ".$mda 
 		}