Add Skylight's performance data badge

sauloperez · sauloperez · commit aab3ddd192ce · 2018-06-04T11:33:01.000+02:00
This not only shows response time of TO's problematic responses but it is
also a requirement for Skylight to display TO in their showcase page.
diff --git a/README.md b/README.md
@@ -1,4 +1,4 @@
-# TimeOverflow [![Build Status](https://travis-ci.org/coopdevs/timeoverflow.svg)](https://travis-ci.org/coopdevs/timeoverflow) [![Code Climate](https://codeclimate.com/github/timeoverflow/timeoverflow/badges/gpa.svg)](https://codeclimate.com/github/timeoverflow/timeoverflow)
+# TimeOverflow [![View performance data on Skylight](https://badges.skylight.io/problem/grDTNuzZRnyu.svg)](https://oss.skylight.io/app/applications/grDTNuzZRnyu) [![Build Status](https://travis-ci.org/coopdevs/timeoverflow.svg)](https://travis-ci.org/coopdevs/timeoverflow) [![Code Climate](https://codeclimate.com/github/timeoverflow/timeoverflow/badges/gpa.svg)](https://codeclimate.com/github/timeoverflow/timeoverflow)
 #### www.timeoverflow.org
 
 :globe_with_meridians: Read this [in English](docs/README.en.md)

Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`		`-# TimeOverflow [![Build Status](https://travis-ci.org/coopdevs/timeoverflow.svg)](https://travis-ci.org/coopdevs/timeoverflow) [![Code Climate](https://codeclimate.com/github/timeoverflow/timeoverflow/badges/gpa.svg)](https://codeclimate.com/github/timeoverflow/timeoverflow)`
	`1`	`+# TimeOverflow [![View performance data on Skylight](https://badges.skylight.io/problem/grDTNuzZRnyu.svg)](https://oss.skylight.io/app/applications/grDTNuzZRnyu) [![Build Status](https://travis-ci.org/coopdevs/timeoverflow.svg)](https://travis-ci.org/coopdevs/timeoverflow) [![Code Climate](https://codeclimate.com/github/timeoverflow/timeoverflow/badges/gpa.svg)](https://codeclimate.com/github/timeoverflow/timeoverflow)`
`2`	`2`	`#### www.timeoverflow.org`
`3`	`3`
`4`	`4`	`:globe_with_meridians: Read this [in English](docs/README.en.md)`