Following the sphinx-autoapi integration with docfx guide, they suggest installing docfx using the following command:
dnu commands install docfx
Did DNU get retired - I just ended up using chocolatey, but it seems like global commands have been dropped in .NET Core CLI. Hoping someone can confirm what happened to .NET Utilities.
choco install docfx
The dnvm repository says it's obsolete, but the dotnet repository isn't really providing a command translation. This Microsoft article on migrating says there's no equivalent dotnet install command.
Installing dependencies
As of v1, the .NET Core CLI tools don't have an install command for installing dependencies. In order to install a package from NuGet, you would need to add it as a dependency to your project.json file and then run dotnet restore.
This other answer confirms that it's obsolete/replaced, but that dnu/dnx can still be used.