added prefix scan and fixed logout issue

pkg/db/blacklist.go

@@ -21,15 +21,13 @@ func (db *DB) Check(sig string) (ok bool) {
 
 func (db *DB) Map() (list jwt.BlacklistMap, err error) {
 	list = make(jwt.BlacklistMap)
-	err = db.store.ForEach(func(k string, v []byte) error {
-		if trim, ok := hasTrimPrefix(k, blacklistPrefix); ok {
-			var exp int64
-			err := db.store.Unmarshal(v, &exp)
-			if err != nil {
-				return err
-			}
-			list[trim] = exp
+	err = db.store.ForEachPrefix(blacklistPrefix, func(k string, v []byte) error {
+		var exp int64
+		err := db.store.Unmarshal(v, &exp)
+		if err != nil {
+			return err
 		}
+		list[k] = exp
 		return nil
 	})
 	return