RFR: 39: Use the lastUpdated field of pull requests to avoid unnecessary polls

[Robin Westberg via github.com]

Hi all,

Please review the following change that introduces an in-memory cache of the lastUpdated field of pull requests, to avoid unnecessary polls.

Best regards,
Robin

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Commits:
 - 252da95f:	Add PullRequestUpdateCache

Pull request:
http://git.openjdk.java.net/skara/pull/25

Webrev:
https://openjdk.github.io/cr/skara/25/webrev.00

Patch:
http://git.openjdk.java.net/skara/pull/25.diff

Fetch command:
git fetch https://github.com/openjdk/skara.git pull/25/head:pull/25