DG MS; added subscriber model for ostatus interop

app/models/subscriber.rb

@@ -0,0 +1,8 @@
+class Subscriber
+  include MongoMapper::Document
+
+  key :url
+
+  validates_presence_of :url
+
+end

spec/models/subscriber_spec.rb

@@ -0,0 +1,12 @@
+require File.dirname(__FILE__) + '/../spec_helper'
+
+describe Subscriber do
+  it 'should require a url' do
+    n = Subscriber.new
+    n.valid?.should be false
+    
+    n.url = "http://clown.com/"
+
+    n.valid?.should be true
+  end
+end