updated code of conduct and minor addition in contrib

CONTRIBUTING.md

@@ -2,7 +2,7 @@ Contributing to Composer
 ========================
 
 Please note that this project is released with a
-[Contributor Code of Conduct](http://contributor-covenant.org/version/1/1/0/).
+[Contributor Code of Conduct](http://contributor-covenant.org/version/1/2/0/).
 By participating in this project you agree to abide by its terms.
 
 Reporting Issues
@@ -42,6 +42,8 @@ Contributing policy
 Fork the project, create a feature branch, and send us a pull request.
 
 To ensure a consistent code base, you should make sure the code follows
-the [PSR-2 Coding Standards](http://www.php-fig.org/psr/psr-2/).
+the [PSR-2 Coding Standards](http://www.php-fig.org/psr/psr-2/). You can also
+run [php-cs-fixer](https://github.com/FriendsOfPHP/PHP-CS-Fixer) with the
+configuration file that can be found in the project root directory.
 
-If you would like to help, take a look at the [list of issues](https://github.com/composer/composer/issues).
+If you would like to help, take a look at the [list of open issues](https://github.com/composer/composer/issues).

README.md

@@ -45,7 +45,6 @@ Updating Composer
 Running `php composer.phar self-update` or equivalent will update a phar
 install to the latest version.
 
-
 Community
 ---------
 
@@ -56,7 +55,7 @@ For support, Stack Overflow also offers a good collection of
 [Composer related questions](https://stackoverflow.com/questions/tagged/composer-php).
 
 Please note that this project is released with a
-[Contributor Code of Conduct](http://contributor-covenant.org/version/1/1/0/).
+[Contributor Code of Conduct](http://contributor-covenant.org/version/1/2/0/).
 By participating in this project and its community you agree to abide by those terms.
 
 Requirements