RFR: 59: Implement summary command

[Robin Westberg via github.com]

Hi all,

Please review this change that implements the possibility to add a summary to a commit message.

Best regards,
Robin

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Commits:
 - 275c8ea3:	Implement a summary command

Pull request:
https://git.openjdk.java.net/skara/pull/46

Webrev:
https://webrevs.openjdk.java.net/skara/46/webrev.00

Patch:
https://git.openjdk.java.net/skara/pull/46.diff

Fetch command:
git fetch https://git.openjdk.java.net/skara pull/46/head:pull/46