Merge pull request #1906 from groupboard/patch-1

Add Groupboard

non-free.md

@@ -17,6 +17,7 @@
 ## Communication Systems
 
 - [Dialog](https://dlg.im) `⊘ Proprietary` - Handy and feature-rich multi-device solution with native mobile clients, SIP integration, chatbots, 3rd-party integrations. It brings communication efficiency without sacrificing privacy. Works in closed circuit, encrypts push notifications. ([Demo](https://dlg.im/en/download)) `Scala/Go`
+- [Groupboard](https://www.groupboard.com) `⊘ Proprietary` - Online whiteboard, audio/video conferencing, screen sharing, shared code editing and optional session recording/playback.
 - [HipChat](https://www.atlassian.com/software/hipchat) `⊘ Proprietary` - A team chat solution with 1:1 chat audio and video, third party integration and more. `PHP/Python`
 - [PrivMX WebMail](https://privmx.com) - an alternative private mail system - web-based, end-to-end encrypted by design, self-hosted, decentralized, uses independent PKI. Easy to install and administrate, freeware, open-source. `PHP`