There is a new plugin available called pimatic-telegram. The plugin provides a device which processes commands send from the messaging client, and it provides a rule action
send <type> telegram to [recipient list] "message content", as well as a rule predicate
when telegram received "message", which can be used to trigger actions in the rule system
The plugin requires an apiToken for a Telegram bot you need to create, and the Chat ID for the recipient of the telegram messages. Instructions and more details on possibilities can be found on the plugin page.
Source can be found on GitHub: https://github.com/SenTzu01/pimatic-telegram/ . If you encounter any issues, or have a feature request I would appreciate you posting them there, to allow for tracking and planning. Of course the forum can be used to discuss enhancements in the appropriate section.