.gitignore file for CodeIgniter 3

What about the application/config directory? Should I .gitignore only the plataform specific files (e.g. database.php)?
I found the following question in stackoverflow http://stackoverflow.com/questions/18115...odeigniter where the suggestion is using an environment directory inside config directory for these files. Also I've received the advice from a colleague that I should .gitignore the entire application/config directory, but this seems weird because I don't feel confortable by ignoring the routes.php file for instance. What is the best practice about this?