Include username in response header (for use by nginx auth_request)

login.go

@@ -57,6 +57,7 @@ func httpBasicAuth(w http.ResponseWriter, r *http.Request) {
 			w.WriteHeader(http.StatusUnauthorized)
 			w.Write([]byte(err.Error()))
 		} else {
+			w.Header().Set("X-Remote-User", user)
 			w.WriteHeader(http.StatusOK)
 			for _, e := range entries {
 				for _, v := range e.Values {