Trailing whitespace false positive under windows platform is described https://bitbucket.org/logilab/pylint/issue/55/ and resolved, though the fix has not been released yet.
For your other problem, W0613 is not impacted by the ignored-argument-names configuration, but by dummy-variables-rgx whose default has been changed in 1.0 to match only '_', not any identifier with leading underscore. This particular change/issue is discuted on https://bitbucket.org/logilab/pylint/issue/98/local-variables-with-leading-underscore.