[HttpFoundation] updated get() signature to get($key, $default = null, $first = true)
[HttpFoundation] updated get() signature to get($key, $default = null, $first = true)

This is more consistent with the get() method of ParameterBag

symfony/http-foundation,symfony/HttpFoundation,ygerasimov/HttpFoundation,oswaldderiemaecker/HttpFoundation,mneuhaus/HttpFoundation,nichdu/HttpFoundation