Some changes to get ready to add `all_after_pass`

The most important one is that the file inspector is moved from plugin's
root to the runner.
Add `all_after_pass` option
Fix small gotcha with all_after_pass option

If the guard rule actually specifies all test files, we don't want to
rerun the whole suite after success (even if the option is set).
Merge remote-tracking branch 'upstream/master' into all_after_pass
Merge branch 'master' into all_after_pass
Merge pull request #101 from deivid-rodriguez/all_after_pass

Implement `all_after_pass` option
Remove rubysl from tests Gemfiles
Allow Rubinius to fail
Bump to 2.2.0