[Gemspec] add cocoapods-downloader

cocoapods.gemspec

@@ -28,8 +28,8 @@ Gem::Specification.new do |s|
 
   # Link with the version of CocoaPods-Core
   s.add_runtime_dependency 'cocoapods-core',       "= #{Pod::VERSION}"
-
   s.add_runtime_dependency 'claide',               '~> 0.1'
+  s.add_runtime_dependency 'cocoapods-downloader', '~> 0.1'
   s.add_runtime_dependency 'xcodeproj',            '~> 0.4.1'
 
   s.add_runtime_dependency 'faraday',       '~> 0.8.1'