[MERGE] Move skipped test detection to TestCase, and make reporting use an addSkip method as per testtools.

[Bundle Buggy]

Bundle Buggy has detected this merge request.

For details, see: 
http://bundlebuggy.aaronbentley.com/project/bzr/request/%3C1235876923.27820.44.camel%40lifeless-64%3E
Project: Bazaar