let the user set the domain title and description

spec/unit/templates/domain_all_settings.xml

@@ -1,5 +1,7 @@
 <domain type='kvm' xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0'>
   <name></name>
+  <title>title</title>
+  <description>description</description>
   <uuid></uuid>
   <memory></memory>
   <vcpu cpuset='1-4,^3,6'>1</vcpu>

spec/unit/templates/domain_custom_cpu_model.xml

@@ -1,5 +1,7 @@
 <domain type='' xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0'>
   <name></name>
+  <title></title>
+  <description></description>
   <uuid></uuid>
   <memory></memory>
   <vcpu>1</vcpu>

spec/unit/templates/domain_defaults.xml

@@ -1,5 +1,7 @@
 <domain type='' xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0'>
   <name></name>
+  <title></title>
+  <description></description>
   <uuid></uuid>
   <memory></memory>
   <vcpu>1</vcpu>

spec/unit/templates/domain_spec.rb

@@ -27,6 +27,8 @@ describe 'templates/domain' do
 
   context 'when all settings enabled' do
     before do
+      domain.title = 'title'
+      domain.description = 'description'
       domain.instance_variable_set('@domain_type', 'kvm')
       domain.cpu_mode = 'custom'
       domain.cpu_feature(name: 'AAA', policy: 'required')