2.0.0

• This release aligns the PSR7Csrf\CSRFCheckerMiddleware implementation to
  the PSR-15 php-fig/http-server-middleware
  specification.

  This means that the signature of PSR7Csrf\CSRFCheckerMiddleware
  changed, and therefore you need to look for usages of this class and verify
  if the new signature is compatible with your API

  Specifically, PSR7Csrf\CSRFCheckerMiddleware#__invoke() was removed.

• The minimum supported PHP version has been raised to 7.1.0

• the PSR7Csrf\Factory::createDefaultCSRFCheckerMiddleware() method now has
  a mandatory argument, which is the response to be produced in case of failed
  CSRF validation. This argument is mandatory, since PSR7Csrf won't couple you
  to a specific PSR-7 implementation.