Cookbook on how to make a new fixer
minor #782 Cookbook on how to make a new fixer (dericofilho)

This PR was squashed before being merged into the 1.3-dev branch (closes #782).

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Cookbook on how to make a new fixer

Addresses FriendsOfPHP/PHP-CS-Fixer#682

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d77df61 Cookbook on how to make a new fixer