Ability to pass a client to the bot

Changed every instance of a DefaultClient to a Client stored in the bot.

bot.go

@@ -1,19 +1,27 @@
 // Package tgbotapi has bindings for interacting with the Telegram Bot API.
 package tgbotapi
 
+import "net/http"
+
 // BotAPI has methods for interacting with all of Telegram's Bot API endpoints.
 type BotAPI struct {
 	Token   string      `json:"token"`
 	Debug   bool        `json:"debug"`
 	Self    User        `json:"-"`
 	Updates chan Update `json:"-"`
+	Client  http.Client `json:"-"`
 }
 
 // NewBotAPI creates a new BotAPI instance.
 // Requires a token, provided by @BotFather on Telegram
-func NewBotAPI(token string) (*BotAPI, error) {
+func NewBotAPI(token string, client http.Client) (*BotAPI, error) {
+	if client == nil {
+		client = &http.Client{}
+	}
+
 	bot := &BotAPI{
-		Token: token,
+		Token:  token,
+		Client: client,
 	}
 
 	self, err := bot.GetMe()

methods.go

@@ -131,7 +131,7 @@ type WebhookConfig struct {
 // MakeRequest makes a request to a specific endpoint with our token.
 // All requests are POSTs because Telegram doesn't care, and it's easier.
 func (bot *BotAPI) MakeRequest(endpoint string, params url.Values) (APIResponse, error) {
-	resp, err := http.PostForm("https://api.telegram.org/bot"+bot.Token+"/"+endpoint, params)
+	resp, err := bot.Client.PostForm("https://api.telegram.org/bot"+bot.Token+"/"+endpoint, params)
 	if err != nil {
 		return APIResponse{}, err
 	} else {
@@ -190,15 +190,14 @@ func (bot *BotAPI) UploadFile(endpoint string, params map[string]string, fieldna
 
 	w.Close()
 
-	req, err := http.NewRequest("POST", "https://api.telegram.org/bot"+bot.Token+"/"+endpoint, &b)
+	req, err := bot.Client.NewRequest("POST", "https://api.telegram.org/bot"+bot.Token+"/"+endpoint, &b)
 	if err != nil {
 		return APIResponse{}, err
 	}
 
 	req.Header.Set("Content-Type", w.FormDataContentType())
 
-	client := &http.Client{}
-	res, err := client.Do(req)
+	res, err := bot.Client.Do(req)
 	if err != nil {
 		return APIResponse{}, err
 	}