Fix examples using undefined function
Fix examples using undefined function

As done for a single example in jedisct1/swift-sodium#26

opfeffer/swift-sodium,ziogaschr/swift-sodium,ziogaschr/swift-sodium,jedisct1/swift-sodium,ziogaschr/swift-sodium,blochberger/swift-sodium,opfeffer/swift-sodium,opfeffer/swift-sodium,jedisct1/swift-sodium,ziogaschr/swift-sodium,blochberger/swift-sodium,jedisct1/swift-sodium,opfeffer/swift-sodium,blochberger/swift-sodium,blochberger/swift-sodium