Dvc: update/uninstall: add these commands?

[jorgeorpinel]

From https://github.com/iterative/dvc.org/issues/702#issuecomment-543536849

• dvc update - depending on how DVC was installed, the process is different and you may forget how it was installed and finding out exactly may not always be so trivial. Maybe we can simplify this by providing a self-update (version upgrade) command? (We already have an update notice.)
• dvc uninstall - same but for completely removing DVC from the system. Maybe leaving global config unless --config is used.

[jorgeorpinel]

Per #2611 it seems we already detect most of the kinds of installs.

[ghost]

@jorgeorpinel , my experience with update commands are not nice at all. I think it is not worth it.
uninstall is also a weird one :thinking: .

I'm not sure what's the experience of the rest, but with mine, I'd hesitate to add this.

[shcheklein]

@jorgeorpinel agreed with @mroutis on this one. It's not very common for CLI tools to have a special command for this. Neither it is easy to implement to make it work reliably.

[shcheklein]

closing this for now. I think it too early and too complicated to have these commands

[jorgeorpinel]

OK, iterative/dvc.org/issues/702 should be enough then. Thanks!