added sister projects

Author: peterwilli

README.md

@@ -77,4 +77,10 @@ What you need:
 - Make a channel, any place you like (bot needs to be able to post to it, so make sure has write permissions there). Name it something like `gallery`
 - Right-click on the channel and click "Copy ID"
 - Paste the channel ID in `shareChannelID` in the bot's `config.yml`. Restart bot if its running!
-- Now you and your members can use `/share` for showcasing your fine art!
+- Now you and your members can use `/share` for showcasing your fine art!
+
+# Sister projects
+
+These are co-developed with Thingy!
+
+- [Diffusers executor](https://github.com/peterwilli/DiffusersExecutor)