readme: Link to darwin.network and the testnet

README.md

@@ -12,7 +12,7 @@ Oragono is a fork of the [Ergonomadic](https://github.com/edmund-huber/ergonomad
 [![Freenode #oragono](https://img.shields.io/badge/Freenode-%23oragono-1e72ff.svg?style=flat)](https://www.irccloud.com/invite?channel=%23oragono&hostname=irc.freenode.net&port=6697&ssl=1)
 [![Crowdin](https://d322cqt584bo4o.cloudfront.net/oragono/localized.svg)](https://crowdin.com/project/oragono)
 
-[darwin.network](https://irc.darwin.network/) is running Oragono in production if you want to take a look.
+[darwin.network](https://irc.darwin.network/) and [testnet.oragono.io](ircs://testnet.oragono.io:6697/#chat) are running Oragono in production if you want to take a look.
 
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