[Suggestion] Custom Links on the Homepage!

[danperks]

Hey, just started using Umbrel and I'm wanting to add some more Docker containers to my system.
I feel like it'd be a nice feature to have external or 3rd-party links on the home page, either to other docker apps outside of Umbrel or to links on the Internet.
Would be willing to give it a go myself and throw a pull request up if people are onboard, but the devs have better things to be doing!