Adding VMware Fusion Support For The 1.2 Branch

This PR uses some moderately crude techniques to ensure that you can vagrant up --provider=vmware_fusion. It requires Vagrant 1.2.7 and vagrant-vmware-fusion 0.8.3 or higher.

It likely does not work with private networks (e.g. `config.vm.network :private_network, ip: "192.168.33.10"`).