Smart doorbell integration for Ritto TwinBus

This project has been deployed and in use for over a year now, and has been working great! I've even modified things to not only notify my phone, but also to notify the NSPanel we put downstairs. Overall, I'd say this project is a success.

However, there's one big feature that has never worked: buzzing someone in. When you click the `Open Door` button, I can hear the relay click, but I must have messed something up in the wiring, because the door never buzzes. As of right now, it is only effective in notifying based on doorbell presses. This still is useful enough that I haven't wanted to take it out of commission in order to troubleshoot, but it is only half of the stated goal of the project. I'll have to revisit this later.

I've made sure that everything is pushed to the GitLab project, so have a look there if you're interested! I'll post again if/when I manage to diagnose the `Open Door` issue.

I've added a link to a new GitLab project containing the hardware designs for this project! Feel free to check them out, and give me any feedback you have!

Also, I tried installing the remote yesterday, but apparently I fried my optocoupler at some point. I'm waiting for replacements to come in, but then I should be able to finally get this working!