Add functionality to download community dictionaries

[kara-louise]

As you are aware, there are currently two community dictionaries. Downloading them means going to their respective GitHub repos, extracting the files manually ETC.
Whilst this isn't too hard to do, I think it would be handy if the driver had the option to automate this for you. It could also notify you of updates and ask if you would like to download the current version.

[ultrasound1372]

There is an add-on that Tyler Spivey made I think to do this though I don't have it, it was sort of just shared around via dropbox links. I imagine the way it works is the GitHub API. To make things simple you could use releases probably, so they aren't getting updates with every commit, but maybe there could be an option to do that too. I'd hope that that function of the GitHub API doesn't require tokens of any kind, since you're viewing public metadata on public repositories.