RFR: vcs: add support for cherry picking

[Robin Westberg]

On Mon, 26 Oct 2020 15:55:15 GMT, Erik Helin <ehelin at openjdk.org> wrote:

> Hi all,
> 
> please review this patch that adds support for "cherry picking" commits to `Repository`.
> 
> Testing:
> - [x] Added two new unit tests
> 
> Thanks,
> Erik

Looks good!

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Marked as reviewed by rwestberg (Reviewer).

PR: https://git.openjdk.java.net/skara/pull/921