Fix token color customization for CodeRay >= 1.1.0

See: https://github.com/rubychan/coderay/commit/e2acec3ef141725d2fc264e56d1aa18e838c6acf
     https://github.com/pry/pry/issues/1012#issuecomment-29213405
Compare version numbers properly
Merge pull request #409 from c0nspiracy/fix-coderay-customization

Fix token color customization for CodeRay >= 1.1.0