Update default platforms for generated kitchen.yml

- Ubuntu 14.04 is now a year old
- CentOS 7.1 is the current 7.x release; 7.x is the current CentOS release

lib/chef-dk/skeletons/code_generator/templates/default/kitchen.yml.erb

@@ -6,8 +6,12 @@ provisioner:
   name: chef_zero
 
 platforms:
-  - name: ubuntu-12.04
-  - name: centos-6.5
+  - name: ubuntu-14.04
+  - name: centos-7.1
+    # https://github.com/test-kitchen/kitchen-vagrant/issues/165
+    driver_config:
+      box: opscode-centos-7.1
+      box_url: box_url: http://opscode-vm-bento.s3.amazonaws.com/vagrant/<%= ENV.fetch("VAGRANT_DEFAULT_PROVIDER", "virtualbox") %>/opscode_centos-7.1_chef-provisionerless.box
 
 suites:
   - name: default