Add support for Rackspace's Extract Archive API call

See http://docs.rackspace.com/files/api/v1/cf-devguide/content/Extract_Archive-d1e2338.html
for documentation on the API call

lib/fog/rackspace/requests/storage/extract_archive.rb

@@ -0,0 +1,39 @@
+require 'fog'
+module Fog
+  module Storage
+    class Rackspace
+      class Real
+
+        # Extract Archive
+        #
+        # See http://docs.rackspace.com/files/api/v1/cf-devguide/content/Extract_Archive-d1e2338.html
+        #
+        # ==== Parameters
+        # * container<~String>      - Name for container, should be < 256 bytes and must not contain '/'
+        # * data<~String|File>      - file to upload
+        # * archive_format<~String> - "tar", "tar.gz", or "tar.bz2"
+        
+        # @raise [Fog::Storage::Rackspace::NotFound] - HTTP 404
+        # @raise [Fog::Storage::Rackspace::BadRequest] - HTTP 400
+        # @raise [Fog::Storage::Rackspace::InternalServerError] - HTTP 500
+        # @raise [Fog::Storage::Rackspace::ServiceError]
+        def extract_archive(container, data, archive_format)
+          data = Fog::Storage.parse_data(data)
+          headers = data[:headers]
+
+          params = { :body => data[:body], :query => {"extract-archive" => archive_format} }
+
+          params.merge!(
+            :expects    => 200,
+            :idempotent => true,
+            :headers    => headers,
+            :method     => 'PUT',
+            :path       => "#{Fog::Rackspace.escape(container.to_s)}"
+          )
+
+          request(params)
+        end
+      end
+    end
+  end
+end

lib/fog/rackspace/storage.rb

@@ -41,6 +41,7 @@ module Fog
       request :put_dynamic_obj_manifest
       request :put_static_obj_manifest
       request :post_set_meta_temp_url_key
+      request :extract_archive
 
       module Common
         def apply_options(options)