Don't include ? in token generation

capture.go

@@ -34,7 +34,7 @@ func (c *Client) Capture(cp *CaptureParams) string {
 	// Calculate token
 	h := md5.New()
 	ue, _ := url.QueryUnescape(u.RawQuery)
-	io.WriteString(h, "?"+ue)
+	io.WriteString(h, ue)
 	io.WriteString(h, c.Secret)
 	token := hex.EncodeToString(h.Sum(nil))