Update vagrant config to use Ubuntu 18.04

Vagrantfile

@@ -4,7 +4,7 @@
 Vagrant.configure("2") do |config|
   # use official ubuntu image for virtualbox
   config.vm.provider "virtualbox" do |vb, override|
-    override.vm.box = "ubuntu/xenial64"
+    override.vm.box = "ubuntu/bionic64"
     override.vm.synced_folder ".", "/srv/openstreetmap-website"
     vb.customize ["modifyvm", :id, "--memory", "1024"]
     vb.customize ["modifyvm", :id, "--cpus", "2"]
@@ -13,13 +13,13 @@ Vagrant.configure("2") do |config|
 
   # use third party image and NFS sharing for lxc
   config.vm.provider "lxc" do |_, override|
-    override.vm.box = "generic/ubuntu1604"
+    override.vm.box = "generic/ubuntu1804"
     override.vm.synced_folder ".", "/srv/openstreetmap-website", :type => "nfs"
   end
 
   # use third party image and NFS sharing for libvirt
   config.vm.provider "libvirt" do |_, override|
-    override.vm.box = "generic/ubuntu1604"
+    override.vm.box = "generic/ubuntu1804"
     override.vm.synced_folder ".", "/srv/openstreetmap-website", :type => "nfs"
   end
 

script/vagrant/setup/provision.sh

@@ -16,12 +16,12 @@ apt-get update
 apt-get upgrade -y
 
 # install packages as explained in INSTALL.md
-apt-get install -y ruby2.3 libruby2.3 ruby2.3-dev \
+apt-get install -y ruby2.5 libruby2.5 ruby2.5-dev \
                      libmagickwand-dev libxml2-dev libxslt1-dev nodejs \
                      apache2 apache2-dev build-essential git-core \
                      postgresql postgresql-contrib libpq-dev postgresql-server-dev-all \
                      libsasl2-dev imagemagick phantomjs
-gem2.3 install bundler
+gem2.5 install rake bundler
 
 ## install the bundle necessary for openstreetmap-website
 pushd /srv/openstreetmap-website