Remove old xcconfig generator, it is now unused

lib/cocoapods.rb

@@ -66,7 +66,6 @@ module Pod
     autoload :ModuleMap,               'cocoapods/generator/module_map'
     autoload :PrefixHeader,            'cocoapods/generator/prefix_header'
     autoload :UmbrellaHeader,          'cocoapods/generator/umbrella_header'
-    autoload :XCConfig,                'cocoapods/generator/xcconfig'
     autoload :AppTargetHelper,         'cocoapods/generator/app_target_helper'
   end
 

lib/cocoapods/generator/xcconfig.rb

-module Pod
-  module Generator
-    # Generates Xcode configuration files. A configuration file is generated
-    # for each Pod and for each Pod target definition. The aggregates the
-    # configurations of the Pods and define target specific settings.
-    #
-    module XCConfig
-      autoload :AggregateXCConfig,  'cocoapods/generator/xcconfig/aggregate_xcconfig'
-      autoload :PodXCConfig,        'cocoapods/generator/xcconfig/pod_xcconfig'
-      autoload :XCConfigHelper,     'cocoapods/generator/xcconfig/xcconfig_helper'
-    end
-  end
-end

spec/unit/generator/xcconfig_spec.rb

-require File.expand_path('../../../spec_helper', __FILE__)
-
-module Pod
-  describe Generator::XCConfig do
-  end
-end