Add Qunar to ADOPTORS.md
Qunar (https://qunar.com) is the leading travel booking service in China. They
use CoreDNS for service discovery of the GPU machine learning cloud they build
with TensorFlow and Kubernetes.
There is a very nice talk in KubeCon 2017, presented by Ye Lu:
* [Sky Betting & Gaming](http://engineering.skybettingandgaming.com) uses CoreDNS for Kubernetes cluster DNS.
* [Kismia](https://kismia.com) uses CoreDNS for Kubernetes cluster DNS.
* [Admiral](https://getadmiral.com) uses CoreDNS to handle geographic DNS requests for our public-facing microservices.
+* [Qunar](https://qunar.com) uses CoreDNS for service discovery of its GPU machine learning cloud with TensorFlow and Kubernetes.
* [seansean2](https://web.mit.edu) uses coreDNS in production at MIT for DNS.
