DIAL support

[hensm]

Provide support for DIAL 1st screen apps.

[NewsGuyTor]

DIAL support would be awesome, DIAL devices are likely way more common than pure Chromecast devices.

I found these links that would be helpful for adding DIAL:
https://source.chromium.org/chromium/chromium/src/+/main:chrome/browser/media/router/discovery/dial/README.md

https://github.com/chunyeow/chromecast/blob/master/pychromecast/dial.py

https://github.com/fraunhoferfokus/peer-dial

Doesn't seem that hard, relatively speaking, to implement.

Edit: Found this, seems like the best resource:
https://github.com/MarcoLucidi01/ytcast/

[hensm]

It seems relatively straightforward.

Would need to figure out a good way to abstract device handling since I think there are some Chromecast-specific assumptions there.

The DIAL part of the Cast SDK would need implementing so we know which applications to launch, though I've not looked into that much.

I'm not sure when I'll have time to work on this, but PRs are welcome in the meantime.

[Topkek-190]

ytcast seems to have implemented this properly.