Prevent "vagrant up" from running on Vagrant 1.0.x after Vagrant 1.1+
has upgraded the .vagrant file into a .vagrant directory -- otherwise,
orphan VMs can be created in VirtualBox
Fix warning from newer versions of Vagrant:

"The 'v-root' shared folders have been renamed to 'vagrant-root'.
Assuming you meant 'vagrant-root'..."
Rename machine from "myproject" to "lucid"
Add "precise" machine to support Ubuntu 12.04 (Precise)