Fixes #1046

vcsim: add EventManager.QueryEvents

In progress.Reader emit final report on EOF.

vcsim: add Destroy method for Folder and Datacenter types

This regression was introduced by 585cf5e , where the DistributedVirtualSwitch
FetchDVPorts wrapper was added to the object package. The new method did not
include the optional 'Criteria' param, so no filtering was applied to the
dvs.portgroup.info command.  The command would panic on uplink portgroups, which
are normally filtered out by default.  But the same panic would happen 0.15 if
the '-uplinkPort' flag is given.

This change also adds an uplink portgroup to simulator switches, which would
reproduce the issue.

The dvs.portgroup.info command now has support for using the '-json' and '-dump' flags.

Fixes #1059
Fixes #1060

Fix dvs.portgroup.info filtering

Add goreleaser to automate release process

The QueryVirtualDiskInfo_TaskResponse can be in the "internalvim25" namespace,
rather than "vim25", which lead to a panic as the 'Res' field would be nil.
Add the same workaround we use for this issue with CreateChildDisk_TaskResponse,
an "InternalRes" field in the "internalvim25" namespace.

Fixes #1066

Avoid possible panic in QueryVirtualDiskInfo