Error handling. Vendoring

Signed-off-by: Ettore Dreucci <ettore.dreucci@gmail.com>

vendor/gopkg.in/tucnak/telebot.v2/stickers.go

@@ -0,0 +1,23 @@
+package telebot
+
+// Sticker object represents a WebP image, so-called sticker.
+type Sticker struct {
+	File
+
+	Width  int `json:"width"`
+	Height int `json:"height"`
+
+	Thumbnail    *Photo        `json:"thumb,omitempty"`
+	Emoji        string        `json:"emoji,omitempty"`
+	SetName      string        `json:"set_name,omitempty"`
+	MaskPosition *MaskPosition `json:"mask_position,omitempty"`
+}
+
+// MaskPosition describes the position on faces where
+// a mask should be placed by default.
+type MaskPosition struct {
+	Feature MaskFeature `json:"point"`
+	XShift  float32     `json:"x_shift"`
+	YShift  float32     `json:"y_shift"`
+	Scale   float32     `json:"scale"`
+}