Before, we use delta disk based on vmdk in image_cache when creating vm.
In theory, creating a machine like this is faster and occupies less storage.
However, it may also affect performance and definitely cannot change the
size of the system disk.
Now, we copy disk from vmdk in image_cache to solve above questions.
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
