ngit clone

I was thinking that a `ngit clone ....` command might be useful.

Usage:

```bash

$ ngit clone NADDR|REPO_NAME

```

where `NADDR` is the naddr of the kind 30617 git announcement event and `REPO_NAME` can be:

* just the repository name, and it would default to searching it on gitworkshop.dev

* `@usename:repo` where username would be resolved using the logged in user's contact list (if there are no ambiguities)

* `npub|nprofile|nip05:repo`

The command would call `git clone` using the first provided clone git repository, using others as fail-overs. It would also set non-primary clone repositories as other git remotes using `git remote add`.

What do you all think? If you like it, I would like to take a shot at implementing it.