RFR: Allow reverse mapping of census namespace users

[Robin Westberg via github.com]

Hi all,

Please review this small change that adds the possibility of mapping from a contributor to the corresponding namespace id.

Best regards,
Robin

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Commits:
 - 23434d67:	Allow reverse mapping of census namespace users

Pull request:
https://git.openjdk.java.net/skara/pull/115

Webrev:
https://webrevs.openjdk.java.net/skara/115/webrev.00

Patch:
https://git.openjdk.java.net/skara/pull/115.diff

Fetch command:
git fetch https://git.openjdk.java.net/skara pull/115/head:pull/115