[1/?] Allow student IDs > 6 digits

lib/validation.php

@@ -125,7 +125,7 @@ function validSID($SID, $override)
             return true;
         }
     } else {
-        if (!preg_match("/^[0-9]*$/", $SID) || strlen($SID) != 6) {
+        if (!preg_match("/^[0-9]{6,}$/", $SID)) {
             $error = "Invalid student ID";
             return false;
         } elseif (sidUsed($SID)) {