add back rack-cache

Gemfile

@@ -4,6 +4,7 @@ source :rubygems
 
 gem 'unicorn'
 gem 'rack-ssl', '~> 1.3'
+gem 'rack-cache'
 
 group :development, :test do
   gem 'rake', '~> 0.9.2'

Gemfile.lock

@@ -44,6 +44,8 @@ GEM
     listen (0.5.3)
     multi_json (1.3.6)
     rack (1.4.1)
+    rack-cache (1.2)
+      rack (>= 0.4)
     rack-ssl (1.3.2)
       rack
     raindrops (0.10.0)
@@ -69,6 +71,7 @@ DEPENDENCIES
   compass
   debugger
   foreman
+  rack-cache
   rack-ssl (~> 1.3)
   rake (~> 0.9.2)
   rake-pipeline!

lib/travis/web/app.rb

@@ -1,5 +1,6 @@
 require 'rack'
 require 'rack/ssl'
+require 'rack/cache'
 require 'delegate'
 require 'time'
 
@@ -105,6 +106,7 @@ class Travis::Web::App
     def builder
       builder = Rack::Builder.new
       builder.use Rack::SSL if environment == 'production'
+      builder.use Rack::Cache
       builder.use Rack::Deflater
       builder.use Rack::Head
       builder.use Rack::ConditionalGet