Added images to the first and last step of the wizard

lib/wizard/builder.rb

@@ -9,6 +9,8 @@ class Wizard
       return @wizard unless SiteSetting.wizard_enabled? && @wizard.user.try(:staff?)
 
       @wizard.append_step('locale') do |step|
+        step.banner = "welcome.png"
+
         languages = step.add_field(id: 'default_locale',
                                    type: 'dropdown',
                                    required: true,
@@ -164,7 +166,9 @@ class Wizard
 
       DiscourseEvent.trigger(:build_wizard, @wizard)
 
-      @wizard.append_step('finished')
+      @wizard.append_step('finished') do |step|
+        step.banner = "finished.png"
+      end
       @wizard
     end
 

lib/wizard/step.rb

@@ -1,7 +1,7 @@
 class Wizard
   class Step
     attr_reader :id, :updater
-    attr_accessor :index, :fields, :next, :previous
+    attr_accessor :index, :fields, :next, :previous, :banner
 
     def initialize(id)
       @id = id