Change cache block to accept an optional error
Change cache block to accept an optional error

alecthomas/AwesomeCache,nickoneill/AwesomeCache,namanhams/AwesomeCache,remzr7/AwesomeCache,alecthomas/AwesomeCache,alecthomas/AwesomeCache,RyanTech/AwesomeCache,nickoneill/AwesomeCache,icepy/AwesomeCache,aschuch/AwesomeCache,takeshineshiro/AwesomeCache,RyanTech/AwesomeCache,takeshineshiro/AwesomeCache,icepy/AwesomeCache,remzr7/AwesomeCache,gilesvangruisen/AwesomeCache,gilesvangruisen/AwesomeCache,aschuch/AwesomeCache,takeshineshiro/AwesomeCache,gilesvangruisen/AwesomeCache,nickoneill/AwesomeCache,remzr7/AwesomeCache,icepy/AwesomeCache,namanhams/AwesomeCache