Commits being submitted from stacks are not being signed

[aridokmecian]

Even when commit signing is set up locally commits appear as unverified on Github

[mattprecious]

There's a section in here about how to do this with libgit2: https://blog.gitbutler.com/signing-commits-in-git-explained/

I've only skimmed so far but hopefully it's possible.

[mattprecious]

Came across some things in the docs:

• git_rebase_commit takes git_rebase_options
• Can pass in a git_commit_create_cb
• The docs for that mention git_commit_create_buffer and git_commit_create_with_signature