added PrivMX WebMail

non-free.md

@@ -18,7 +18,7 @@
 
   * [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`
   * [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 administration. Freeware, open-source. `PHP\JavaScript`.
   
 ## Decentralized Network