Implement Cross-Origin Resource Sharing:

* Add Api::ApplicationController
* Route OPTION requests (CORS preflight) to API application controller
* Filter all API requests through #cor_filter in API application
  controller

spec/routing/options_requests_spec.rb

@@ -0,0 +1,11 @@
+require 'spec_helper'
+
+describe '/api OPTIONS requests routing' do
+  it 'routes to Api::ApplicationController#cor_preflight' do
+    { :options => '/api/v0' }.should route_to(
+      :controller => 'api/application',
+      :action => 'cor_preflight',
+      :all => 'v0'
+    )
+  end
+end