Adapt Vagrantfile

- add example for nfs connection
- add libvirt config section for memory setup

Vagrantfile

@@ -24,6 +24,7 @@ Vagrant.configure(2) do |config|
 
   # Share a folder between host and guest
   # config.vm.synced_folder ".", "/vagrant", id: "vagrant-root", owner: "www-data", group: "vagrant"
+  # config.vm.synced_folder ".", "/vagrant", id: "vagrant-root", type: "nfs"
   config.vm.synced_folder ".", "/vagrant", id: "vagrant-root", owner: "www-data", group: "www-data", type: "virtualbox"
 
   # Provider-specific configuration so you can fine-tune various
@@ -40,6 +41,10 @@ Vagrant.configure(2) do |config|
     end
   end
 
+  config.vm.provider :libvirt do |libvirt|
+  	libvirt.memory = server_memory
+  end
+
   # Enable provisioning with a shell script.
   config.vm.provision "shell", path: "./bin/dev/vagrant_provision.sh", privileged: true
     # run: "always"