Update Vagrantfile to work with Vagrant 1.x series
Update gitignore for .vagrant files
Add support for local.conf
Add support for Neutron, by adding a third interface

This will add a third interface, eth1 that will be used
for management - eth2 will be given over to Neutron
Change the cache_dir to not use NFS
Remove mac & mac_prefix
Break out the VM IP prefix into a separate cidr from eth2

Neutron creates a gateway on the same IP as the eth2 interface
that VirtualBox assigns, which mucks up the networking

Instead, pass in the IP of the gateway that VirtualBox assigns eth2
so that we can then override it in the localrc, in
PUBLIC_NETWORK_GATEWAY