RFR: Add support for ready markers to the PR bot as well

[Robin Westberg via github.com]

Hi all,

Please review this change that allows the PR bot to support configurable ready markers, similar to the mlbridge bot.

Best regards,
Robin

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Commits:
 - a6173692:	Add support for ready markers to the PR bot as well

Pull request:
https://git.openjdk.java.net/skara/pull/64

Webrev:
https://webrevs.openjdk.java.net/skara/64/webrev.00

Patch:
https://git.openjdk.java.net/skara/pull/64.diff

Fetch command:
git fetch https://git.openjdk.java.net/skara pull/64/head:pull/64