Added Xcode 8 to Travis builds
Added Xcode 8 to Travis builds

ibm-bluemix-mobile-services/bms-clientsdk-swift-analytics,ibm-bluemix-mobile-services/bms-clientsdk-swift-analytics,ibm-bluemix-mobile-services/bms-clientsdk-swift-analytics,ibm-bluemix-mobile-services/bms-clientsdk-swift-analytics,ibm-bluemix-mobile-services/bms-clientsdk-swift-analytics