Add rake ~> 0.9.0 (for rake/file_list.rb file) to gemspec. Closes #195.

cocoapods.gemspec

@@ -31,6 +31,7 @@ Gem::Specification.new do |s|
   s.add_runtime_dependency 'xcodeproj', '~> 0.1.0'
   s.add_runtime_dependency 'colored', '~> 1.2'
   s.add_runtime_dependency 'escape', '~> 0.0.4'
+  s.add_runtime_dependency 'rake', '~> 0.9.0'
   s.add_development_dependency 'bacon', '~> 1.1'
 
   ## Make sure you can build the gem on older versions of RubyGems too: