First version of the README
First version of the README

Mostly copied from the ibm-bluemix-mobile-services/bms-clientsdk-swift-core README
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