Merge branch '4.0' into 4.1

* 4.0:
  Removed a short article about overriding bundle templates
  Improved the front controller of the HttpCache
  Better docs about overriding third-party translations
  Change form.xxx_bind to form.xxx_submit
  add legacy labels
  Update Best Practices about service config format
  Fix a configuration block in the Doctrine Associations page
  Fix numbering
  add missing label
  Minor typo in csrf.rst
  Update setup.rst

Author: weaverryan