Modified Vagrantfile to use NFS folder sharing

Virtualbox has issues with certain operations on shared folders
using the default sharing mechanism. These are overcome using
NFS sharing.

On Ubuntu, sudo apt-get install nfs-kernel-server

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

Vagrantfile

@@ -33,11 +33,14 @@ Vagrant.configure(2) do |config|
   # your network.
   # config.vm.network "public_network"
 
+  # Virtualbox requires a private network to use NFS
+  config.vm.network "private_network", type: "dhcp"
+
   # Share an additional folder to the guest VM. The first argument is
   # the path on the host to the actual folder. The second argument is
   # the path on the guest to mount the folder. And the optional third
   # argument is a set of non-required options.
-  config.vm.synced_folder ".", "/Firmware"
+  config.vm.synced_folder ".", "/Firmware", type: "nfs"
 
   # Provider-specific configuration so you can fine-tune various
   # backing providers for Vagrant. These expose provider-specific options.