Edited readme
Edited readme

Put emphasis on downloading rather than cloning per PM.

splunk/splunk-sdk-java,splunk/splunk-sdk-java,splunk/splunk-sdk-java,dkelmer/splunk-sdk-java,splunk/splunk-sdk-java,dkelmer/splunk-sdk-java,dkelmer/splunk-sdk-java,dkelmer/splunk-sdk-java,splunk/splunk-sdk-java,dkelmer/splunk-sdk-java,splunk/splunk-sdk-java