[ticket/13063] Introduces a new \phpbb\routing\router class

https://tracker.phpbb.com/browse/PHPBB3-13063
https://tracker.phpbb.com/browse/PHPBB3-12681

Depends on:
- [x] https://github.com/phpbb/phpbb/pull/2921
- [x] https://github.com/phpbb/phpbb/pull/2922

PHPBB3-12681
PHPBB3-13063