Show a message why VM export was skipped while building on VMWare Fusion/Workstation

builder/vmware/iso/step_export.go

@@ -45,6 +45,7 @@ func (s *StepExport) Run(state multistep.StateBag) multistep.StepAction {
 	}
 
 	if c.RemoteType != "esx5" || s.Format == "" {
+		ui.Say("Skipping export of virtual machine (export is allowed only for ESXi and the format needs to be specified)...")
 		return multistep.ActionContinue
 	}
 

website/source/docs/builders/vmware-iso.html.md

@@ -478,7 +478,8 @@ modify as well:
 
 -   `format` (string) - Either "ovf", "ova" or "vmx", this specifies the output
     format of the exported virtual machine. This defaults to "ovf".
-    Before using this option, you need to install `ovftool`.
+    Before using this option, you need to install `ovftool`. This option 
+	works currently only with option remote_type set to "esx5".
 
 ### VNC port discovery