Enable gzip compression on nginx

Enable the gzip compression on nginx to improve performance

config/nginx.conf

@@ -83,6 +83,12 @@ http {
         }
     }
     
+    gzip on;
+    gzip_proxied any;
+    gzip_types text/plain application/xml text/css text/js text/xml application/x-javascript text/javascript application/json application/xml+rss;
+    gzip_vary on;
+    gzip_disable "msie6";
+    
     # Include other server configs
     include /etc/nginx/conf.d/*.conf;
 }