This command is confusing in name and function. Rather than creating
a hard fork of a repository, with a new identity, it pushes the
default branch to the local user's namespace.
Deprecate it and add some help text.
The `help` module is no longer needed, since `clap` handles that.
This meant that the re-exports of each command's `ABOUT` could be removed and
the `const`s can now be private.
Lorenz Leutgeb
Fintan Halpenny
Matthias Beyer