Fix lint warnings

Author: ekalinin

ghdoc.go

@@ -99,7 +99,9 @@ func (doc *GHDoc) Convert2HTML() error {
 	if doc.Debug {
 		htmlFile := doc.Path + ".debug.html"
 		doc.d("Convert2HTML: write html file: " + htmlFile)
-		ioutil.WriteFile(htmlFile, []byte(htmlBody), 0644)
+		if err := ioutil.WriteFile(htmlFile, []byte(htmlBody), 0644); err != nil {
+			return err
+		}
 	}
 	doc.html = htmlBody
 	return nil

internals.go

@@ -57,7 +57,10 @@ func httpPost(urlPath, filePath, token string) (string, error) {
 	defer file.Close()
 
 	body := &bytes.Buffer{}
-	io.Copy(body, file)
+	_, err = io.Copy(body, file)
+	if err != nil {
+		return "", err
+	}
 
 	req, err := http.NewRequest("POST", urlPath, body)
 	if err != nil {