add quay.io as another Docker option

README.md

@@ -1,4 +1,4 @@
-Gogs - Go Git Service [![Build Status](https://travis-ci.org/gogits/gogs.svg?branch=master)](https://travis-ci.org/gogits/gogs)
+Gogs - Go Git Service [![Build Status](https://travis-ci.org/gogits/gogs.svg?branch=master)](https://travis-ci.org/gogits/gogs) [![Docker Repository on Quay](https://quay.io/repository/gogs/gogs/status "Docker Repository on Quay")](https://quay.io/repository/gogs/gogs)
 =====================
 
 [![Gitter](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/gogits/gogs?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)

docker/README.md

@@ -1,6 +1,6 @@
 # Docker for Gogs
 
-Visit [Docker Hub](https://hub.docker.com/r/gogs/gogs/) see all available tags.
+Visit [Docker Hub](https://hub.docker.com/r/gogs/gogs/) or [QUAY](https://quay.io/repository/gogs/gogs) see all available tags.
 
 ## Usage