fix#161
Current request router was organically grown, and is getting messier and messier with each addition.
This router cover exaustively existing API endpoints (with exceptions listed in [#161(comment)](https://git.deuxfleurs.fr/Deuxfleurs/garage/issues/161#issuecomment-1773) either because new and old api endpoint can't feasabily be differentied, or it's more lambda than s3).
Co-authored-by: Trinity Pointard <trinity.pointard@gmail.com>
Reviewed-on: https://git.deuxfleurs.fr/Deuxfleurs/garage/pulls/163
Reviewed-by: Alex <alex@adnab.me>
Co-authored-by: trinity-1686a <trinity.pointard@gmail.com>
Co-committed-by: trinity-1686a <trinity.pointard@gmail.com>
