Set correct HTTP codes for some auth-related errors.
Set correct HTTP codes for some auth-related errors.

spulec/moto,william-richard/moto,william-richard/moto,spulec/moto,william-richard/moto,william-richard/moto,william-richard/moto,spulec/moto,whummer/moto,whummer/moto,spulec/moto,whummer/moto,whummer/moto,william-richard/moto,spulec/moto,spulec/moto,whummer/moto,whummer/moto