Tar / zip a directory instead of sending individual files.

[stefins]

Is your feature request related to a problem? Please describe.
Right now croc send all the individual files in a directory recursively which increases the time to send the directory if it contains many files.
eg. a .git directory

Describe the solution you'd like
The solution I'm suggesting is that to tar / zip the entire directory and send it as an individual file.

Describe alternatives you've considered

Additional context

[schollz]

As far as I can determine, this feature would be incompatible with being able to resume file transfers. But if you know there is a way to do it, feel free to discuss / make a PR

[stefins]

We can define a cli flag to enable this feature

[schollz]

Ah yeah I get it, that makes sense

[stefins]

I'm writing a PR for this!

[schollz]

Ok cool! I was about to so thanks for letting me know. If you have any questions feel free to ask!

[stefins]

Fixed in #488

[nivekuil]

Tested this, much faster and convenient but it doesn't include empty directories, which seems undesirable

[stellarpower]

This is really useful for sending built code as an example. We want to make sure we retain all ownership and permissions, not follow symlinks, and it's a nice feature to have one stage that creates and extracts the tarball. I'd happily forego the ability to resume a botched transfer in cases like this.

[schollz]

Tested this, much faster and convenient but it doesn't include empty directories, which seems undesirable

That sounds like a bug, would you make an issue?