Fixed a bug that always raise the error: "** PACKAGE FAILED ** No Signing Identity Found"

This is my first time writing ruby, so I may be missing something here, but to me it seems like the properties:
signing_identity & provisioning_profile
are never defined on the Class Configuration.

Hence the following exceptions will always be raised.
raise "** PACKAGE FAILED ** No Signing Identity Found" unless @configuration.signing_identity
raise "** PACKAGE FAILED ** No Provisioning Profile Found" unless @configuration.provisioning_profile

I just removed the dependencies on these properties.
Please correct this and let me know if I am wrong.