.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?

There's a method built-into the framework and that's the environment-specific configs. You won't get closer to a "best practice" than that because that's the most flexible solution, but it's natual that you'll get different advices from different people - the whole problem here is that every environment is unique and there's no magic bullet. You just have to pick what works for you.