[Web] Add default sieve accessq

data/web/inc/vars.inc.php

@@ -175,6 +175,9 @@ $MAILBOX_DEFAULT_ATTRIBUTES['pop3_access'] = true;
 // Mailbox has SMTP access by default
 $MAILBOX_DEFAULT_ATTRIBUTES['smtp_access'] = true;
 
+// Mailbox has sieve access by default
+$MAILBOX_DEFAULT_ATTRIBUTES['sieve_access'] = true;
+
 // Mailbox receives notifications about...
 // "add_header" - mail that was put into the Junk folder
 // "reject" - mail that was rejected