Update README for 1.4.0 release
Update README for 1.4.0 release

flandr/s3proxy,kahing/s3proxy,andrewgaul/s3proxy,kahing/s3proxy,flandr/s3proxy,bouncestorage/s3proxy,timuralp/s3proxy,timuralp/s3proxy,bouncestorage/s3proxy,andrewgaul/s3proxy