CLOUDSTACK-1192: GetVmDiskStatsCommand return null as disk I/O statistics does not support xen/vmware
CLOUDSTACK-4266: UI > Infrastructure > clusters > add cluster dialog > if configuration 'vmware.use.dvswitch' is set to false (i.e. override public/guest traffic checkboxes are hidden), hide VSM fields (regardless of another configuration 'vmware.use.nexus.switch').
CLOUDSTACK-4459: fix silly bug, one more time
CLOUDSTACK-4562: addS3/addSwift API is retired (being replaced with addImageStore API) and old configuration 's3.enable'/'swift.enable' has been removed from database. So, remove obsolete UI that calls addS3/addSwift API.