remove logging redundancy

poller.go

@@ -101,7 +101,6 @@ func (p *LongPoller) Poll(b *Bot, dest chan Update, stop chan struct{}) {
 		updates, err := b.getUpdates(p.LastUpdateID+1, p.Limit, p.Timeout, p.AllowedUpdates)
 		if err != nil {
 			b.debug(err)
-			b.debug(ErrCouldNotUpdate)
 			continue
 		}
 

util.go

@@ -4,15 +4,15 @@ import (
 	"bytes"
 	"encoding/json"
 	"fmt"
-	"github.com/pkg/errors"
 	"log"
 	"net/http"
 	"strconv"
+
+	"github.com/pkg/errors"
 )
 
 func (b *Bot) debug(err error) {
-	err = errors.WithStack(err)
-	log.Printf("%+v\n", err)
+	log.Println(err)
 }
 
 func (b *Bot) deferDebug() {