Use VIC API list to show the VCH inventory list

[jak-atx]

trafficstars

Details: Currently we use the VC vSphere API to get the list of VCHs. In order to add additional requested functionality (e.g https://github.com/vmware/vic-ui/issues/322 and https://github.com/vmware/vic-ui/issues/65) we need to utilize the VIC api to display the VCH list.

[AngieCris]

needs a priority @jak-atx @jooskim since we want it before reconfigure upgrade/rollback, we might probably want to mark it at least p2?

[andrewtchin]

need to decide if we should fallback to current way if API is not reachable

[zjs]

Not strictly a pre-req. but if we fix this, we should definitely fix vmware/vic#6792 in the same release.