Update README.md

Author: dvershinin

README.md

@@ -2,6 +2,7 @@
 
 [![Build Status](https://travis-ci.org/GetPageSpeed/ngx_immutable.svg?branch=master)](https://travis-ci.org/GetPageSpeed/ngx_immutable)
 [![Coverity Scan](https://img.shields.io/coverity/scan/GetPageSpeed-ngx_immutable)](https://scan.coverity.com/projects/GetPageSpeed-ngx_immutable)
+[![Buy Me a Coffee](https://img.shields.io/badge/dynamic/json?color=blue&label=Buy%20me%20a%20Coffee&prefix=%23&query=next_time_total&url=https%3A%2F%2Fwww.getpagespeed.com%2Fbuymeacoffee.json&logo=buymeacoffee)](https://www.buymeacoffee.com/dvershinin)
 
 This tiny NGINX module can help improve caching of your public static assets, by setting far future expiration with `immutable` attribute.
 
@@ -20,7 +21,7 @@ Popular frameworks which use cache-busting:
 
 ## Synopsis
 
-```
+```nginx
 http {
     server {
         location /static/ {
@@ -139,4 +140,4 @@ location /static/ {
         immutable off;
     }
 }
-```
+```