Symfony 3.4.0-RC1 released

Symfony 3.4.0-RC1 has just been released. Here is a list of the most important changes: bug #25077 [Bridge/Twig] Let getFlashes starts the session (@MatTheCat) bug #25082 [HttpKernel] Disable container inlining when legacy inlining has been used (@nicolas-grekas) bug #25072 [Bridge/PhpUnit] Remove trailing "n" from ClockMock::microtime(false) (@joky) bug #25069 [Debug] Fix undefined variable $lightTrace (@nicolas-grekas) bug…