fix typo in css_dir
fix typo in css_dir

nonconforme/CodeIgniter-minify,nonconforme/CodeIgniter-minify,reg2005/CodeIgniter-minify,reg2005/CodeIgniter-minify,webhacking/CodeIgniter-minify,nonconforme/CodeIgniter-minify,reg2005/CodeIgniter-minify,slav123/CodeIgniter-minify,slav123/CodeIgniter-minify,michalsn/CodeIgniter-minify,webhacking/CodeIgniter-minify,michalsn/CodeIgniter-minify,webhacking/CodeIgniter-minify,slav123/CodeIgniter-minify,michalsn/CodeIgniter-minify