Added Mailtrain and Slimta

README.md

@@ -219,6 +219,7 @@ _MTAs / SMTP servers_
 * [Postfix](http://www.postfix.org/) - Fast, easy to administer, and secure Sendmail replacement. `IPL` `C`
 * [Qmail](http://www.qmail.org/top.html) - Secure Sendmail replacement. `CC0`
 * [Sendmail](http://www.sendmail.com/sm/open_source/) - Message transfer agent (MTA).
+* [Slimta](http://slimta.org) - Mail Transfer Library built on Python. ([Source Code](https://github.com/slimta/python-slimta)) `MIT License` `Python`
 
 
 #### Mail Delivery Agents
@@ -241,6 +242,7 @@ _Mailing lists servers._
 
 _Mass mailing software - one message to many recipients_
 
+  * [Mailtrain](https://mailtrain.org/) - self hosted newsletter application built on Node.js (v5+) and MySQL (v5.5+ or MariaDB). ([Source Code](https://github.com/andris9/mailtrain)) `GPL-V3.0` `Node.js`
   * [phpList](https://phplist.org) - Newsletter and email marketing with advanced management of subscribers, bounces, and plugins. ([Source Code](https://github.com/phpList/)) `AGPLv3` `PHP`