RFR: Add ReadOnlyRepository::status

[Erik Duveblad via github.com]

Hi all,

this patch adds the method `ReadOnlyRepository::status` and a corresponding unit test.

## Testing
- [x] `sh gradlew test` passes on Linux x86_64

Thanks,
Erik

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Commits:
 - 79edf6dd:	Add ReadOnlyRepository::status

Pull request:
https://git.openjdk.java.net/skara/pull/80

Webrev:
https://webrevs.openjdk.java.net/skara/80/webrev.00

Patch:
https://git.openjdk.java.net/skara/pull/80.diff

Fetch command:
git fetch https://git.openjdk.java.net/skara pull/80/head:pull/80