[Doctrine Bridge] simplify session handler by using main connection
Merge branch '2.3' into 2.4

* 2.3:
  fix docblock
  Fixed incompatibility of x509 auth with nginx
  [Process] Setting STDIN while running should not be possible
  [FrameworkBundle] improve English in RouterMatchCommand
  [Doctrine Bridge] simplify session handler by using main connection

Conflicts:
	src/Symfony/Component/Process/Tests/AbstractProcessTest.php