`jj sparse` is a bit different from other commands in that its `jj
sparse --list` is practically a separate command. Let's make it an
actual subcommand for consistency, and so we can more cleanly add
additional flags for `jj sparse list` in the future. I moved all the
other arguments to `jj sparse set`. I'm not sure if `jj sparse set
--reset` would have been better as `jj sparse reset`, but it is
technically just updating the sparse patterns just like the other
arguments (`--clear`, `--add` , `--remove`).
Let's acknowledge everyone's contributions by replacing "Google LLC"
in the copyright header by "The Jujutsu Authors". If I understand
correctly, it won't have any legal effect, but maybe it still helps
reduce concerns from contributors (though I haven't heard any
concerns).
Google employees can read about Google's policy at
go/releasing/contributions#copyright.
This adds a `jj sparse` command with options to list and manage the
set of paths to include in the working copy. It only supports includes
(postive matches) for now.
I'm not sure "sparse" is the best name for the feature. Perhaps it
would make sense as a subcommand under `jj workspace` - maybe `jj
workspace track`? However, there's also `jj untrack` for removing a
file from the working copy and leaving it in the working copy. I'm
happy to hear suggestions, or we can get back to the naming later.