Adds sponsors to splash

spec/factories/sponsors.rb

@@ -5,6 +5,10 @@ FactoryGirl.define do
     name 'Example sponsor'
     website_url 'http://www.example.com'
     description 'Lorem Ipsum Dolor'
+    logo_file_name 'rails.jpg'
+    logo_file_size 2000
+    logo_content_type 'image/jpeg'
+    logo_updated_at DateTime.current
     sponsorship_level
     conference
   end