Fix linter warnings

Author: thewizardplusplus

.gometalinter.json

@@ -2,5 +2,5 @@
   "Vendor": true,
   "Test": true,
   "EnableAll": true,
-  "Disable": ["dupl"]
+  "Disable": ["dupl", "maligned"]
 }

examples_test.go

@@ -49,6 +49,7 @@ func RunServer() *httptest.Server {
 		request *http.Request,
 	) {
 		if request.URL.Path == "/robots.txt" {
+			// nolint: errcheck
 			fmt.Fprint(writer, `
 				User-agent: go-crawler
 				Disallow: /2