bot: fix entities passing for InputMedia

bot.go

@@ -619,7 +619,12 @@ func (b *Bot) SendAlbum(to Recipient, a Album, opts ...interface{}) ([]Message,
 
 		im := x.InputMedia()
 		im.Media = repr
-		im.ParseMode = sendOpts.ParseMode
+
+		if len(sendOpts.Entities) > 0 {
+			im.Entities = sendOpts.Entities
+		} else {
+			im.ParseMode = sendOpts.ParseMode
+		}
 
 		data, _ = json.Marshal(im)
 		media[i] = string(data)
@@ -915,7 +920,12 @@ func (b *Bot) EditMedia(msg Editable, media Inputtable, opts ...interface{}) (*M
 
 	im := media.InputMedia()
 	im.Media = repr
-	im.ParseMode = sendOpts.ParseMode
+
+	if len(sendOpts.Entities) > 0 {
+		im.Entities = sendOpts.Entities
+	} else {
+		im.ParseMode = sendOpts.ParseMode
+	}
 
 	if thumb != nil {
 		im.Thumbnail = "attach://" + thumbName

media.go

@@ -16,10 +16,11 @@ type Media interface {
 // InputMedia represents a composite InputMedia struct that is
 // used by Telebot in sending and editing media methods.
 type InputMedia struct {
-	Type      string `json:"type"`
-	Media     string `json:"media"`
-	ParseMode string `json:"parse_mode"`
-	Thumbnail string `json:"thumb"`
+	Type      string   `json:"type"`
+	Media     string   `json:"media"`
+	Thumbnail string   `json:"thumb,omitempty"`
+	ParseMode string   `json:"parse_mode,omitempty"`
+	Entities  Entities `json:"caption_entities,omitempty"`
 
 	*Photo
 	*Audio