adds Microformats2::Parser#http_headers and Microformats2::Parser#http_body and saves them from the response

lib/microformats2/parser.rb

@@ -1,13 +1,19 @@
 module Microformats2
   class Parser
-    def parse(html)
-      html = read_html(html)
+    attr_reader :http_headers, :http_body
+
+    def parse(html, headers={})
+      html = read_html(html, headers)
       document = Nokogiri::HTML(html)
       Collection.new(document).parse
     end
 
-    def read_html(html)
-      open(html).read
+    def read_html(html, headers={})
+      open(html, headers) do |response|
+        @http_headers = response.meta if response.respond_to?(:meta)
+        @http_body = response.read
+      end
+      @http_body
     rescue Errno::ENOENT, Errno::ENAMETOOLONG => e
       html
     end