Fix content-type for rss feeds

config.ru

@@ -20,9 +20,9 @@ end
 
 require "adamantium/middleware/header_fix"
 use Adamantium::Middleware::HeaderFix do |headers, env|
-  # if env["REQUEST_METHOD"] == "HEAD"
+  unless headers["Content-Type"].include? "xml"
-  headers["Content-Type"] = "text/html; charset=utf-8"
+    headers["Content-Type"] = "text/html; charset=utf-8"
-  # end
+  end
 end
 
 run Hanami.app