RFR: 320: Add "git skara version" command

[Robin Westberg]

On Thu, 19 Mar 2020 07:42:45 GMT, Erik Helin <ehelin at openjdk.org> wrote:

> Hi all,
> 
> please review this patch that adds a `git skara version` command. I also took
> the opportunity to clean up `git skara help` a bit.
> 
> Testing:
> - Manual testing on Linux x64
> 
> Thanks,
> Erik

Looks good!

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Marked as reviewed by rwestberg (Reviewer).

PR: https://git.openjdk.java.net/skara/pull/520