removed debutils keys from testdata
generated new test keypairs in all possible formats
renamed SubPacket.Type.CreationTime and ExpirationTime to SigCreationTime and SigExpirationTime; added KeyExpirationTime
added new test keypairs to test_PGPKeys.py
modified test slightly to use the changed name for SigCreationTime
modified GPG scripts to use the new test keypairs
generated new keyrings containing the new keys
resigned inline_signed_message with TestRSAKey
resigned signed_message with TestRSAKey