Fingerprint and key generation for multi-part request

e2e/singleUse/mac.go

e2e/singleUse/recipientID.go

e2e/singleUse/requestFingerprint.go

e2e/singleUse/requestFingerprint_test.go

e2e/singleUse/requestKey.go

e2e/singleUse/requestKey_test.go

e2e/singleUse/requestPartFingerprint.go

e2e/singleUse/requestPartFingerprint_test.go

e2e/singleUse/requestPartKey.go

e2e/singleUse/requestPartKey_test.go

e2e/singleUse/tagFingerprint.go