Add basic support for 32-bit VM

toolset/deployment/vagrant/Vagrantfile

@@ -94,11 +94,15 @@ Vagrant.configure("2") do |config|
   config.vm.synced_folder "../../..", "/FrameworkBenchmarks"
   config.vm.network :forwarded_port, guest: 8080, host: 28080
 
-  config.vm.provider :virtualbox do |vb|
+  config.vm.provider :virtualbox do |vb, override|
     vb.customize ["modifyvm", :id, "--memory", "2048"]
     if ENV['TFB_SHOW_VM'] and ENV['TFB_SHOW_VM'] == "true"
       vb.gui = true
     end
+
+    if ENV['TFB_VM_ARCH'] and ENV['TFB_SHOW_VM'] == "32"
+      override.vm.box = "ubuntu/trusty32"
+    end
   end
 
   # Requires the vagrant-aws plugin from github.com/mitchellh/vagrant-aws