Save container files on project's .vagrant folder

[fgrehm]

My projects are stored under /home which is mounted on a separate partition. I also keep my system partition small and having lots of containers' under the default /var/lib/lxc will eat a lot of disk space

[fgrehm]

This is not a good idea as the project's root is shared with the container by default and weird things might happen (like guard trying to watch for changes on the whole rootfs)

The commit above made possible for setting up the rootfs path that gets passed to lxc-create and we are able to drop it anywhere we want.