Use libvirt/KVM by default for vagrant

temporary workaround for #45

vagrant/Vagrantfile

@@ -7,15 +7,22 @@ if DBTYPE != "mysql" && DBTYPE != "postgresql"
 	abort
 end
 
-puts "Using DBTYPE '#{DBTYPE}'"
+PROVIDER = ENV.fetch("GC_PROVIDER", "libvirt") # because VirtualBox is crashing the host in Linux
+BOX = "generic/ubuntu1604"
+if PROVIDER == "virtualbox"
+	BOX = "ubuntu/xenial64"
+end
+
 Vagrant.configure("2") do |config|
 	config.ssh.username = "vagrant"
-	config.vm.box = "ubuntu/xenial64"
-	config.vm.network "forwarded_port", guest: 80, host: 8080
+	config.vm.box = BOX
+	config.vm.network "forwarded_port", guest: 80, host: 80
 	config.vm.network :private_network, ip: "172.27.0.3"
 	config.vm.synced_folder "../", "/vagrant"
-	config.vm.provider "virtualbox" do |provider|
-		provider.gui = false
+	config.vm.provider PROVIDER do |provider|
+		if PROVIDER == "virtualbox"
+			provider.gui = false
+		end
 		provider.cpus = "4"
 		provider.memory = "4096"
 	end

vagrant/bootstrap.sh

@@ -8,6 +8,7 @@ if [ -z "$DBTYPE" ]; then
 	echo "DBTYPE environment variable not set, must be 'mysql' or 'postgresql' (sqlite3 no longer supported)"
 	exit 1
 fi
+echo "Using DBTYPE $DBTYPE"
 
 add-apt-repository -y ppa:gophers/archive
 apt-get -y update && apt-get -y upgrade