README.md: fix version in nginx banner

Author: came88

README.md

@@ -1,5 +1,5 @@
 ![latest 0.7.0](https://img.shields.io/badge/latest-0.7.0-green.svg?style=flat)
-![nginx 1.14.1](https://img.shields.io/badge/nginx-1.14-brightgreen.svg) ![License MIT](https://img.shields.io/badge/license-MIT-blue.svg) [![Build Status](https://travis-ci.org/jwilder/nginx-proxy.svg?branch=master)](https://travis-ci.org/jwilder/nginx-proxy) [![](https://img.shields.io/docker/stars/jwilder/nginx-proxy.svg)](https://hub.docker.com/r/jwilder/nginx-proxy 'DockerHub') [![](https://img.shields.io/docker/pulls/jwilder/nginx-proxy.svg)](https://hub.docker.com/r/jwilder/nginx-proxy 'DockerHub')
+![nginx 1.17.3](https://img.shields.io/badge/nginx-1.17.3-brightgreen.svg) ![License MIT](https://img.shields.io/badge/license-MIT-blue.svg) [![Build Status](https://travis-ci.org/jwilder/nginx-proxy.svg?branch=master)](https://travis-ci.org/jwilder/nginx-proxy) [![](https://img.shields.io/docker/stars/jwilder/nginx-proxy.svg)](https://hub.docker.com/r/jwilder/nginx-proxy 'DockerHub') [![](https://img.shields.io/docker/pulls/jwilder/nginx-proxy.svg)](https://hub.docker.com/r/jwilder/nginx-proxy 'DockerHub')
 
 
 nginx-proxy sets up a container running nginx and [docker-gen][1].  docker-gen generates reverse proxy configs for nginx and reloads nginx when containers are started and stopped.