Add drvier libguestfs to support deploy more operator system,
you can use it by edit host config file add 'image_deploy_driver: libguestfs'.
By the default host-deploy support run three guestfish at the same time.
And host deployer will recycle free guestfish every ten minitues.
cherrypick: release/3.6
1. 修改了host-deployer 使其支持 vmware vddk 的 deploy guest fs 操作。
2. esxi agent python ==> Go
fix(esxi-agent): Fix some bugs and irregular contents
fix(esxi-agent): Partial parameter structure
fix(esxi-agent): Add ovf template and remove some binary file
fix(esxi-agent): Format Code
fix(esxi-agent): fix based on reviewers' comments
fix(esxi-agent): fix host-deployer because of occasional unknown panic
fix: DelayTask should have a new Context
fix(esxi-agent): call hostutils.DelayTask
change '_interface' package to 'iagent' package
fix(esxi-agent): Fix some irregular code