Add source to OutgoingEvent

This patch adds the Source field to the OutgoingEvent, so that
an operator can see which host an event came from.

Fixes: #23
Fixes: #22

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

Update to Go 1.11

Closes: #27

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

Update Travis filename

Signed-off-by: Alex Ellis <alexellis2@gmail.com>

Added ObjectName to OutboundEvent

In certain cases the ManagedObjectReference alone might not be useful,
e.g. when an object is deleted.

This commit adds a new field `objectName` to the outbound JSON data
which serves as additional metadata for the receiver.

Note: ObjectName for certain vSphere objects, e.g. virtual machines, is
only unique within a folder (if applicable) as per the description
[here](https://docs.vmware.com/en/VMware-vSphere/6.7/com.vmware.vsphere.vm_admin.doc/GUID-76E73C62-A973-4839-BB67-AC1817908E6D.html).

This added field should be treated as metadata and not for requests
against vCenter (use `ManagedObjectReference` instead).

Signed-off-by: Michael Gasch <embano1@live.com>

Build instructions for govc and vcsim

Signed-off-by: Michael Gasch <embano1@live.com>