fix integration.test_repository

Fixes `integration.test_repository` failure from http://trac.openmicroscopy.org.uk/ome/ticket/11610 so that there should be no skips or failures at http://hudson.openmicroscopy.org.uk/job/OmeroPy-integration-develop/lastSuccessfulBuild/testReport/test.integration.test_repository/.

Adjusts `PublicRepositoryI.checkId` to detect more security violations.

--no-rebase as FS-specific