merge current_machine_options into config in connect_to_machine

I'm not sure if this is the right thing to do.

In testing the machine_file resource with chef_metal_vsphere 0.3.0.beta.1, the config parameter passed to the driver's connect_to_machine does not contain a machine_options hash.  Without the machine_options, I'm not sure where to obtain ssh_config for the machine.

#am_i_doing_it_right