Fix coveralls and a brittle test

* `#debug?` depends on whether or not the debugger is loaded. The tests for it were brittle and could start to fail if you were running the specs with the debugger loaded.
* On the coveralls UI I'm seeing the same file listed many times.  I think it's because we run all the specs together and then run each individually and the multiple test runs confuses it.

![rspec_rspec-core build 1225 coveralls - code coverage history and statistics](https://f.cloud.github.com/assets/49391/627131/bf507194-cff9-11e2-81a0-adf26993a3ed.jpg)