title: Which symfony auto-generated files should you avoid editing?
body: <p>In the symfony framework, a great many files are auto-generated at various stages of development. Some of these files are meant to be edited and manually-customized while others are meant to never (or very rarely) be hand-edited but instead to change as the result of changes to other configuration or settings files.</p>
  
  <p>Which symfony files fit into this latter category of "avoid hand-editing"? I want to know so I can exclude these files from revision-control. Another reason to know is simply to know which files I should avoid editing.</p>