Cleaner and also safer gitignore. Dodges vendors dir entirely and also...

Cleaner and also safer gitignore.  Dodges vendors dir entirely and also removes sensitive data found in parameters.ini.

Symfony2.gitignore

+app/bootstrap*
 */logs/*
 */cache/*
 web/uploads/*
 web/bundles/*
+vendor/
+app/config/parameters.ini
\ No newline at end of file