Create a Passport Service

[Buwujiu]

Detailed Description

1. parsePassport → return Passport object from content of Passport JWT (string)
2. validatePassport (vs public key) → requires passportBroker config (to fetch public key)
3. can we cache public keys for a period of time? (like a day) → dont need to constantly fetch them
4. getVisas → return list of visa JWTs
5. getPermissionsForPassport → return list of permissions from passport (compiled list of all permissions from all visas, remove duplicates)

Possible Implementation