Adding open-vm-tools to core group

[Bruno Wolff III]

On Tue, May 07, 2013 at 10:48:01 -0700,
   Ravindra Kumar <ravindrakumar at vmware.com> wrote:
>
>It is not required for system to be functional, but it also leaves
>a significant gap in the VM to be fully operational unless Tools are
>installed. I listed out a bunch of functionality that depends on
>open-vm-tools in my other response.

That suggests that it should be in the @standard group, not the @core group.

>If there are strong use cases that don't require that functionality
>then probably it makes sense to not be part of core, otherwise, I think
>it makes more sense to make open-vm-tools part of @core because sooner
>or later users will end up installing these due to one or the other
>use case.

It is only needed by people using some VMs. So not all people who install 
@core are going to need it.