0.10.6

• Full support for PHP 7.3:
  • Support for is_countable() (7888e6e) - https://wiki.php.net/rfc/is-countable
  • Support for JSON_THROW_ON_ERROR (d98c7ca) - https://wiki.php.net/rfc/json_throw_on_error
  • Support for array_key_first()/array_key_last() (f0252a5) - https://wiki.php.net/rfc/array_key_first_last
• Prevent using symfony/console with broken exit code handling (#1548), thanks @duncan3dc!