2016-02-18: always access the latest version

always access the latest version

diff --git a/crawl-wot.scm b/crawl-wot.scm
--- a/crawl-wot.scm
+++ b/crawl-wot.scm
@@ -221,7 +221,7 @@
                      (car (cdr args)))))
     (let ((seed (if (string-index seed-id #\/)
                     seed-id
-                    (string-append "USK" (string-drop seed-id 3) "/WebOfTrust/0"))))
+                    (string-append "USK" (string-drop seed-id 3) "/WebOfTrust/-1")))) ; -1 can also return 0
       ;; (write (download-by-date-hint seed))
       (par-map download-by-date-hint
                (crawl-wot seed)))))